Download Slides05 - Vernon Computer Science

// Java0501.java
// This program (and
the next few programs) demonstrate user keyboard input
JAVA0501.JAVA
// during program execution. This particular program demonstrates keyboard
// input of a string in a text window using the <Expo> class.
Enter name
===>>
Isolde Schram
public class Java0501
{
Name Entered:
Isolde Schram
public static void main (String args[])
{
System.out.println();
System.out.println("JAVA0501.JAVA");
System.out.println();
System.out.print("Enter name ===>> ");
String name = Expo.enterString();
System.out.println();
System.out.println("\nName Entered:
System.out.println();
// Line 1
// Line 2
" + name);
}
}
Line 1 is called the prompt. It asks or “prompts” the user for information.
Line 2 is the line that actually enters the String and stores it in name.
// Java0502.java
JAVA0502.JAVA for
// This program demonstrates how to use Expo.enterString()
// three separate String keyboard inputs.
Enter Line 1
Enter Line 2
Enter Line 3
public class Java0502
{
public static void main (String args[]) Austrid
{
Ingrid
System.out.println("\nJAVA0502.JAVA\n");
Raymond
System.out.print("Enter Line 1 ===>> ");
String input1 = Expo.enterString();
System.out.print("Enter Line 2 ===>> ");
String input2 = Expo.enterString();
System.out.print("Enter Line 3 ===>> ");
String input3 = Expo.enterString();
System.out.println();
System.out.println(input1);
System.out.println(input2);
System.out.println(input3);
System.out.println();
}
}
===>>
===>>
===>>
Austrid
Ingrid
Raymond
// Java0503.java
//
This program demonstrates <String> objects concatenation with
JAVA0503.JAVA
// keyboard entered data.
Enter 1st Number
public
Java0503
Enterclass
2nd
Number
{
===>>
===>>
100
200
public static void main (String args[])
100 + 200 = 100200
{
System.out.println("\nJAVA0503.JAVA\n");
System.out.print("Enter 1st Number ===>> ");
String number1 = Expo.enterString();
System.out.print("Enter 2nd Number ===>> ");
String number2 = Expo.enterString();
String sum = number1 + number2;
System.out.println();
System.out.println(number1 + " + " + number2 + " = " + sum);
System.out.println();
}
}
Addition vs. Concatenation
The problem with the previous program is that
Strings were used instead of ints or doubles.
When the plus sign ( + ) is used with a numerical
value, like an int or a double, it performs addition.
However, when the plus sign is used with Strings,
it joins the Strings together.
This is called String Concatenation.
// Java0504.java
//
This program uses the Expo.enterInt() method to enter integers from
JAVA0504.JAVA
// the keyboard. It is now possible to correctly add the two numbers.
Enter 1st Number
public
Java0504
Enterclass
2nd
Number
{
===>>
===>>
100
200
public static void main (String args[])
100 + 200 = 300
{
System.out.println("\nJAVA0504.JAVA\n");
System.out.print("Enter 1st Number ===>> ");
int number1 = Expo.enterInt();
System.out.print("Enter 2nd Number ===>> ");
int number2 = Expo.enterInt();
int sum = number1 + number2;
System.out.println();
System.out.println(number1 + " + " + number2 + " = " + sum);
System.out.println();
}
}
// Java0505.java
// This program demonstrates how to use Expo.enterDouble()
for three
JAVA0505.JAVA
// separate double keyboard inputs, which are used to display the mean.
Enter Number 1 ===>>
public class Java0505
Enter Number 2 ===>>
{
Enter Number 3 ===>>
public static void main (String args[])
{
1.1
System.out.println("\nJAVA0505.JAVA\n");
22.22
System.out.print("Enter Number 1 ===>> ");
333.333
1.1
22.22
333.333
double n1 = Expo.enterDouble();
System.out.print("Enter Number 2 ===>> ");
The mean is 118.88433333333334
double n2 = Expo.enterDouble();
System.out.print("Enter Number 3 ===>> ");
double n3 = Expo.enterDouble();
System.out.println();
System.out.println(n1);
System.out.println(n2);
System.out.println(n3);
double mean = (n1 + n2 + n3) / 3;
System.out.println();
System.out.println("The mean is " + mean);
System.out.println();
}
}
// Java0506.java
JAVA0506.JAVA
// This program demonstrates
how to use Expo.enterChar() which is ideal
// for entering a single letter.
Enter First Name:
===>> John
Enter Middle Initial: ===>> Q
public class Java0506
Enter Last Name:
===>> Public
{
public static void main (String args[])
Your full name is: John Q. Public
{
System.out.println("\nJAVA0506.JAVA\n");
System.out.print("Enter First Name: ===>> ");
String firstName = Expo.enterString();
System.out.print("Enter Middle Initial: ===>> ");
char middleInitial = Expo.enterChar();
System.out.print("Enter Last Name: ===>> ");
String lastName = Expo.enterString();
System.out.println();
System.out.println("Your full name is: " + firstName + " " +
middleInitial + ". " + lastName);
System.out.println();
}
}
Expo class Input Methods
Expo.enterInt() is used to enter an int from the text screen.
Expo.enterDouble() is used to enter a double from the text screen.
Expo.enterString() is used to enter a String from the text screen.
Expo.enterChar() is used to enter a char from the text screen.
Program Flow
Program Flow follows the exact
sequence of listed program statements,
unless directed otherwise by a Java
control structure.
Types of
Control Structures
•
Simple Sequence
•
Selection also called:
-
•
Decision Making
Conditional Branching
Alternation
Repetition also called:
-
Looping
Iteration
Simple Sequence
Program Statement
Program Statement
Program Statement
Program Statement
One-Way Selection
Program Statement
Condition
True
False
Program Statement
Program Statement
Program Statement
Two-Way Selection
Program Statement
True
Condition
False
Program Statement
Program Statement
Program Statement
Program Statement
Multiple-Way Selection
Selection Variable
Selection Constant
No Match
Selection Constant
No Match
Selection Constant
Match
Match
Match
No Match
Program Statement
Program Statement
Program Statement
Program Statement
Repetition
Program Statement
Program Statement
Program Statement
Condition
True
False
Program Statement
Conditional Statement
Definition
A conditional statement is a
program expression that
evaluates to true or false.
Most conditional statements
require a relational operator.
All conditions must be placed
inside (parentheses).
Relational Operators
Name
Operator Expression Evaluates
Greater than
==
!=
<
>
Less than or
equals
<=
Greater than
or equals
>=
Equals
Not Equals
Less than
5 == 5
5 == 10
true
false
50 != 25
100 != 100
true
false
100 < 200
200 < 100
200 > 100
200 > 200
100 <= 200
200 <= 200
200 <= 100
100 >= 200
200 >= 200
200 >= 100
true
false
true
false
true
true
false
false
true
true
Important Note:
The relational operators shown on the previous
slide will be used in the Java example programs
that demonstrate the different control structures.
Be careful not to confuse the equality operator
( == ) with the assignment operator ( = ).
Assignment ( = )
Equality ( == )
int x = 10;
if (x == 10)
Assigns a the value of 10 to x.
Checks if x is equal to 10.
// Java0507.java
JAVA0507.JAVA
// This program demonstrates one-wayJAVA0507.JAVA
selection with <if>.
// Run the program twice. First with Sales equals to 300,000
Enter
Sales time
===>>
300000
Enter Sales ===>>
// and a second
with Sales
equals 500,000.
Christmas
bonus:
0.0
Christmas bonus:
public class Java0507
{
public static void main (String args[])
{
System.out.println("\nJAVA0507.JAVA\n");
System.out.print("Enter Sales ===>> ");
double sales = Expo.enterDouble();
double bonus = 0.0;
System.out.println();
if (sales >= 500000.0)
bonus = 1000.0;
System.out.println("Christmas bonus:
System.out.println();
}
}
" + bonus);
500000
1000.0
Indentation Rule:
Java syntax uses freeform program style.
Program statements may be placed on multiple
lines with or without indentation.
By convention, control structures and their
conditional statements are placed on one line.
The program statement that is executed, if the
condition is true, is placed on the next line, and
indented below the conditional statement.
if(sales >= 500000)
bonus = 1000;
if(sales >=500000) bonus = 1000;
Important Note:
Headings are NOT program statements
and therefore do not get a semicolon!
This applies to class headings and
method headings.
It also applies to
control structure
headings!
// Java0508.java
//
This program demonstrates one-way selectionJAVA0508.JAVA
with <if>.
JAVA0508.JAVA
// It also shows that only one statement is controlled. Run the program twice.
//
FirstSales
with ===>>
Sales equals
time
with
Sales500000
equals to 500,000.
Enter
300000to 300,000 and then a 2nd
Enter
Sales
===>>
CONGRATULATIONS!
public
class
You sold
halfJava0508
a million dollars in merchandise!
{You will receive a $1000 Christmas Bonus!
public static void main (String args[])
Keep up the good work!
{
CONGRATULATIONS!
You sold half a million dollars in merchandise!
You will receive a $1000 Christmas Bonus!
Keep up the good work!
System.out.println("\nJAVA0508.JAVA\n");
1000.0
System.out.print("Enter
Sales ===>> ");
double sales = Expo.enterDouble(); Christmas bonus: 1000.0
double bonus = 0.0;
Christmas bonus:
if (sales >= 500000.0)
System.out.println();
System.out.println("CONGRATULATIONS!");
System.out.println("You sold half a million dollars in merchandise!");
System.out.println("You will receive a $1000 Christmas Bonus!");
System.out.println("Keep up the good work!");
bonus = 1000.0;
System.out.println();
System.out.println("Christmas bonus:
System.out.println();
}
}
" + bonus);
// Java0509.java
JAVA0509.JAVA
JAVA0509.JAVA
// This program demonstrates one-way
selection with <if>.
// It fixes the logic problem of the previous program with block structure by using braces.
Enter Sales
===>>
300000
Enter Sales
===>>
500000
public class Java0509
{Christmas bonus:
0.0
CONGRATULATIONS!
public static void main (StringYou
args[])
sold half a million dollars in merchandise!
{
You will receive a $1000 Christmas Bonus!
System.out.println("\nJAVA0509.JAVA\n");
Keep up the good work!
System.out.print("Enter Sales ===>> ");
double sales = Expo.enterDouble();
Christmas bonus:
1000.0
double bonus = 0.0;
if (sales >= 500000.0)
{
System.out.println();
System.out.println("CONGRATULATIONS!");
System.out.println("You sold half a million dollars in merchandise!");
System.out.println("You will receive a $1000 Christmas Bonus!");
System.out.println("Keep up the good work!");
bonus = 1000.0;
}
System.out.println();
System.out.println("Christmas bonus:
System.out.println();
}
}
" + bonus);
One-Way Selection
General Syntax:
if (condition true)
execute program statement
Specific Examples:
if (counter > 100)
System.out.println("Counter exceeds 100");
if (savings >= 10000)
{
System.out.println("It’s skiing time");
System.out.println("Let’s pack");
System.out.println("Remember your skis");
}
Two-Way Selection
Real Life Example
I35W takes you
to Fort Worth.
I35E takes you
to Dallas.
Interstate 35 splits into I35W and I35E just North of Hillsboro.
// Java0510.java
//
This program demonstrates two-wayJAVA0510.JAVA
selection with <if..else>.
JAVA0510.JAVA
// Run the program twice: First with 1200, then with 1000.
Enter SAT
===>>
1200
Enter SAT
===>>
1000
public class Java0510
{
Youpublic
arestatic
admitted
You are not admitted
void main (String args[])
{
System.out.println("\nJAVA0510.JAVA\n");
System.out.print("Enter SAT ===>> ");
int sat = Expo.enterInt();
System.out.println();
if (sat >= 1100)
System.out.println("You are admitted");
else
System.out.println("You are not admitted");
System.out.println();
}
}
// Java0511.java
JAVA0511.JAVA
JAVA0511.JAVA
// This program demonstrates two-way selection
with <if..else>.
// Multiple statements require the use of block structure.
Enter
SATprogram
===>>twice:
1100First with 1100,
Enter
SAT 1099.
===>> 1099
// Run the
then with
public class Java0511
{You are admitted
You are not admitted
public static
voidstart
main (String
args[])Please try again when your SAT improves
Orientation
will
in June
{
System.out.println("\nJAVA0511.JAVA\n");
System.out.print("Enter SAT ===>> ");
int sat = Expo.enterInt();
System.out.println();
if (sat >= 1100)
{
System.out.println("You are admitted");
System.out.println("Orientation will start in June");
}
else
{
System.out.println("You are not admitted");
System.out.println("Please try again when your SAT improves");
}
}
}
System.out.println();
Two-Way Selection
General Syntax:
if (condition true)
execute first program statement
else // when condition is false
execute second program statement
Specific Example:
if (gpa >= 90.0)
System.out.println ("You’re an honor graduate");
else
System.out.println ("You’re not an honor graduate");
Multi-Way Selection
Real Life Example
// Java0512.java
// This program demonstrates multi-way selection with <switch> and <case>.
// This program compiles, but displays illogical output.
public class Java0512
{
public static void main (String args[])
{
System.out.println("\nJAVA0512.JAVA\n");
System.out.print("Enter Letter Grade ===>> ");
char grade = Expo.enterChar();
System.out.println();
switch (grade)
{
case 'A' : System.out.println("90 .. 100 Average");
case 'B' : System.out.println("80 .. 89 Average");
case 'C' : System.out.println("70 .. 79 Average");
case 'D' : System.out.println("60 .. 69 Average");
case 'F' : System.out.println("Below 60 Average");
}
System.out.println();
}
}
JAVA0512.JAVA
Enter Letter Grade
90 ..
80 ..
70 ..
60 ..
Below
===>>
A
===>>
C
===>>
F
100 Average
89 Average
79 Average
69 Average
60 Average
JAVA0512.JAVA
Enter Letter Grade
70 .. 79 Average
60 .. 69 Average
Below 60 Average
JAVA0512.JAVA
Enter Letter Grade
Below 60 Average
// Java0513.java
// This program demonstrates multi-way selection with <switch> and <case>.
// The program adds <break> and <default>. The use of <break> is required
// for logical output. The <default> case occurs when no other case matches.
public class Java0513
{
public static void main (String args[])
{
System.out.println("\nJAVA0513.JAVA\n");
System.out.print("Enter Letter Grade ===>> ");
char grade = Expo.enterChar();
System.out.println();
switch (grade)
{
case 'A'
: System.out.println("90 .. 100 Average");
case 'B'
: System.out.println("80 .. 89 Average");
case 'C'
: System.out.println("70 .. 79 Average");
case 'D'
: System.out.println("60 .. 69 Average");
case 'F'
: System.out.println("Below 60 Average");
default
: System.out.println("No Match Found");
}
System.out.println();
}
}
break;
break;
break;
break;
break;
JAVA0513.JAVA
Enter Letter Grade
JAVA0513.JAVA
===>>
A
Enter Letter Grade
90 .. 100 Average
80 .. 89 Average
JAVA0513.JAVA
JAVA0513.JAVA
Enter Letter Grade
===>>
C
Enter Letter Grade
70 .. 79 Average
60 .. 69 Average
JAVA0513.JAVA
JAVA0513.JAVA
Enter Letter Grade
Below 60 Average
===>>
F
Enter Letter Grade
No Match Found
===>>
B
===>>
D
===>>
Q
Program Note
In order to focus on the important and
relevant parts of each program, several
programs will not be shown in their
entirety. Rather, a segment of the
program will be shown that focuses on
the key point. You have the complete
programs on your computer.
// Java0514.java
// This program demonstrates that multiple program statements
// can be placed between the <case> and the <break> statements.
System.out.print("Enter Letter Grade ===>> ");
char grade = Expo.enterChar();
switch (grade)
{
case 'A' :
System.out.println("90 .. 100 Average");
System.out.println("Excellent!");
break;
case 'B' :
System.out.println("80 .. 89 Average");
System.out.println("Good");
break;
case 'C' :
System.out.println("70 .. 79 Average");
System.out.println("Fair");
break;
case 'D' :
System.out.println("60 .. 69 Average");
System.out.println("Poor");
break;
case 'F' :
System.out.println("Below 60 Average");
System.out.println("Bad");
break;
default :
System.out.println("No Match Found");
}
JAVA0514.JAVA
Enter Letter Grade
===>>
B
===>>
C
===>>
d
80 .. 89 Average
Good
JAVA0514.JAVA
Enter Letter Grade
70 .. 79 Average
Fair
JAVA0514.JAVA
Enter Letter Grade
No Match Found
// Java0515.java
// This program demonstrates how to allow for both capital and lowercase letters,
switch (grade)
{
case 'A' :
case 'a' :
System.out.println("90 .. 100 Average");
System.out.println("Excellent!");
break;
case 'B' :
case 'b' :
System.out.println("80 .. 89 Average");
System.out.println("Good");
break;
case 'C' :
case 'c' :
System.out.println("70 .. 79 Average");
System.out.println("Fair");
break;
case 'D' :
case 'd' :
System.out.println("60 .. 69 Average");
System.out.println("Poor");
break;
case 'F' :
case 'f' :
System.out.println("Below 60 Average");
System.out.println("Bad");
break;
default :
System.out.println("No Match Found");
}
JAVA0515.JAVA
Enter Letter Grade
===>>
A
===>>
a
90 .. 100 Average
Excellent!
JAVA0515.JAVA
Enter Letter Grade
90 .. 100 Average
Excellent!
// Java0516.java
// This program demonstrates multi-way selection can
// also be controlled with an <int> variable.
public class Java0516
{
public static void main (String args[])
{
System.out.println("\nJAVA0516.JAVA\n");
System.out.print("What grade are you in? ===>> ");
int grade = Expo.enterInt();
System.out.println();
switch (grade)
{
case 9 : System.out.println("Freshman"); break;
case 10 : System.out.println("Sophomore"); break;
case 11 : System.out.println("Junior"); break;
case 12 : System.out.println("Senior"); break;
default : System.out.println("You are not in high school.");
}
System.out.println();
}
}
JAVA0516.JAVA
What grade are you in?
JAVA0516.JAVA
===>>
9
What grade are you in?
Freshman
Sophomore
JAVA0516.JAVA
JAVA0516.JAVA
What grade are you in?
Junior
===>>
11
What grade are you in?
===>>
10
===>>
12
===>>
3
Senior
JAVA0516.JAVA
What grade are you in?
You are not in high school.
// Java0517.java
// This is a more complicated program where <int> is being used
// to control multi-way selection.
// In this example multiple cases can yield the same result.
System.out.print("What grade are you in? ===>> ");
int grade = Expo.enterInt();
switch (grade)
{
case 0 : case 1 : case 2 : case 3 : case 4 : case 5 :
System.out.println("Elementary School");
break;
case 6 : case 7 : case 8 :
System.out.println("Middle School");
break;
case 9 : case 10 : case 11 : case 12 :
System.out.println("High School");
break;
case 13 : case 14 : case 15 : case 16 :
System.out.println("College");
break;
default :
System.out.println("Graduate School");
}
JAVA0517.JAVA
What grade are you in?
JAVA0517.JAVA
===>>
7
What grade are you in?
Middle School
High School
JAVA0517.JAVA
JAVA0517.JAVA
What grade are you in?
===>>
2
What grade are you in?
Elementary School
College
JAVA0517.JAVA
JAVA0517.JAVA
What grade are you in?
Graduate School
===>>
18
What grade are you in?
Elementary School
===>>
11
===>>
13
===>>
0
// Java0518.java
JAVA0518.JAVA
// This program demonstrates multi-way selection can
// also be controlled with a <String> variable.
Enter
first
of Leon
Schram's children.
// This isthe
a new
featurename
with of
Javaone
Version
7 (jdk 1.7.0).
===>>
Maria
This
Schram's older daughter.
public is
classMr.
Java0518
{
public static void main (String args[])
{
System.out.println("\nJAVA0518.JAVA\n");
System.out.print("Enter the first name of one of Leon Schram's children. ===>> ");
String firstName = Expo.enterString();
System.out.println();
switch (firstName)
{
case "John" : System.out.println("This is Mr. Schram's older son."); break;
case "Greg" : System.out.println("This is Mr. Schram's younger son."); break;
case "Maria" : System.out.println("This is Mr. Schram's older daughter."); break;
case "Heidi" : System.out.println("This is Mr. Schram's younger daughter."); break;
default
: System.out.println("This is not one of Mr. Schram's children.");
}
System.out.println();
}
}
// Java0519.java
// This is a more complicated program where <String> is being used
// to control multi-way selection.
// In this example multiple cases can yield the same result.
System.out.print("Enter the first name of someone in Leon Schram's family. ===>> ");
String firstName = Expo.enterString();
switch (firstName)
{
case "Isolde" :
System.out.println("This is Mr. Schram's wife.");
break;
case "John" :
case "Greg" :
System.out.println("This is one of Mr. Schram's sons.");
break;
case "Maria" :
case "Heidi" :
System.out.println("This is one of Mr. Schram's daughters.");
break;
case "Mike" :
case "David" :
System.out.println("This is one of Mr. Schram's sons-in-law.");
break;
case "Diana" :
System.out.println("This is Mr. Schram's daughter-in-law.");
break;
case "Jessica" :
case "Haley" :
case "Brenda" :
case "Mari" :
System.out.println("This is one of Mr. Schram's granddaughters.");
break;
case "Anthony" :
case "Alec" :
case "Maddox" :
case "Jaxon" :
case "Braxton" :
System.out.println("This is one of Mr. Schram's grandsons.");
break;
case "Austrid" :
case "Ingrid" :
System.out.println("This is one of Mr. Schram's sisters.");
break;
case "Remy" :
System.out.println("This is Mr. Schram's brother.");
break;
case "Darlene" :
case "Kassi" :
case "Holli" :
System.out.println("This is one of Mr. Schram's nieces.");
break;
case "Gene" :
case "Sean" :
case "Blake" :
System.out.println("This is one of Mr. Schram's nephews.");
break;
default :
System.out.println("This is not someone in Mr. Schram's immediate family.");
System.out.println("Make sure you spell the name correctly and only capitalize the first letter.");
}
JAVA0519.JAVA
Enter the first name of someone in Leon Schram's family.
===>>
Braxton
===>>
Blake
This is one of Mr. Schram's grandsons.
JAVA0519.JAVA
Enter the first name of someone in Leon Schram's family.
This is one of Mr. Schram's nephews.
Multiple-Way Selection
General Syntax
switch(selectionVariable)
{
case selectionConstant:
program statement;
program statement;
:
:
:
break;
case selectionConstant:
program statement;
program statement;
:
:
:
break;
default
program statement;
program statement;
:
:
:
}
Multiple-Way Selection
Specific Example
switch(courseGrade)
{
case 'A' : points = 4; break;
case 'B' : points = 3; break;
case 'C' : points = 2; break;
case 'D' : points = 1; break;
case 'F' : points = 0; break;
default : System.out.println("Error");
}
The default statement is used to handle the situation when a
proper match is not found. Frequently an error message is
used to indicate that no match was found.
// Java0520.java
JAVA0520.JAVA
// This program displays 40 identical lines very inefficiently
Eat at Joe's friendly
Eat at Joe's friendly
// with 40 separate println statements.
Eat at Joe's friendly
Eat
Eat
Eat
Eat
Eat
Eat
Eat
Eat
Eat
Eat
Eat
Eat
Eat
Eat
Eat
Eat
Eat
Eat
Eat
Eat
Eat
Eat
Eat
Eat
Eat
Eat
Eat
Eat
Eat
Eat
Eat
Eat
Eat
Eat
Eat
Eat
Eat
Eat
Eat
Eat
at
at
at
at
at
at
at
at
at
at
at
at
at
at
at
at
at
at
at
at
at
at
at
at
at
at
at
at
at
at
at
at
at
at
at
at
at
at
at
at
Joe's
Joe's
Joe's
Joe's
Joe's
Joe's
Joe's
Joe's
Joe's
Joe's
Joe's
Joe's
Joe's
Joe's
Joe's
Joe's
Joe's
Joe's
Joe's
Joe's
Joe's
Joe's
Joe's
Joe's
Joe's
Joe's
Joe's
Joe's
Joe's
Joe's
Joe's
Joe's
Joe's
Joe's
Joe's
Joe's
Joe's
Joe's
Joe's
Joe's
friendly
friendly
friendly
friendly
friendly
friendly
friendly
friendly
friendly
friendly
friendly
friendly
friendly
friendly
friendly
friendly
friendly
friendly
friendly
friendly
friendly
friendly
friendly
friendly
friendly
friendly
friendly
friendly
friendly
friendly
friendly
friendly
friendly
friendly
friendly
friendly
friendly
friendly
friendly
friendly
diner
diner
diner
diner
diner
diner
diner
diner
diner
diner
diner
diner
diner
diner
diner
diner
diner
diner
diner
diner
diner
diner
diner
diner
diner
diner
diner
diner
diner
diner
diner
diner
diner
diner
diner
diner
diner
diner
diner
diner
diner
diner
diner
for
for
for
for
for
for
for
for
for
for
for
for
for
for
for
for
for
for
for
for
for
for
for
for
for
for
for
for
for
for
for
for
for
for
for
for
for
for
for
for
for
for
for
the
the
the
the
the
the
the
the
the
the
the
the
the
the
the
the
the
the
the
the
the
the
the
the
the
the
the
the
the
the
the
the
the
the
the
the
the
the
the
the
the
the
the
best
best
best
best
best
best
best
best
best
best
best
best
best
best
best
best
best
best
best
best
best
best
best
best
best
best
best
best
best
best
best
best
best
best
best
best
best
best
best
best
best
best
best
lunch
lunch
lunch
lunch
lunch
lunch
lunch
lunch
lunch
lunch
lunch
lunch
lunch
lunch
lunch
lunch
lunch
lunch
lunch
lunch
lunch
lunch
lunch
lunch
lunch
lunch
lunch
lunch
lunch
lunch
lunch
lunch
lunch
lunch
lunch
lunch
lunch
lunch
lunch
lunch
lunch
lunch
lunch
public class Java0520
{
public static void main(String args[])
{
System.out.println("\nJAVA0501.JAVA\n");
System.out.println("Eat at Joe's friendly diner for the best lunch value");
System.out.println("Eat at Joe's friendly diner for the best lunch value");
System.out.println("Eat at Joe's friendly diner for the best lunch value");
System.out.println("Eat at Joe's friendly diner for the best lunch value");
System.out.println("Eat at Joe's friendly diner for the best lunch value");
System.out.println("Eat at Joe's friendly diner for the best lunch value");
System.out.println("Eat at Joe's friendly diner for the best lunch value");
System.out.println("Eat at Joe's friendly diner for the best lunch value");
System.out.println("Eat at Joe's friendly diner for the best lunch value");
System.out.println("Eat at Joe's friendly diner for the best lunch value");
System.out.println("Eat at Joe's friendly diner for the best lunch value");
System.out.println("Eat at Joe's friendly diner for the best lunch value");
System.out.println("Eat at Joe's friendly diner for the best lunch value");
System.out.println("Eat at Joe's friendly diner for the best lunch value");
System.out.println("Eat at Joe's friendly diner for the best lunch value");
:
:
:
:
:
:
:
:
:
:
:
:
:
:
:
:
value
value
value
value
value
value
value
value
value
value
value
value
value
value
value
value
value
value
value
value
value
value
value
value
value
value
value
value
value
value
value
value
value
value
value
value
value
value
value
value
value
value
value
// Java0521.java
// This program displays 40 identical lines efficiently
// with one println statement and a loop structure.
public class Java0521
{
public static void main(String args[])
{
System.out.println("\nJAVA0521.JAVA\n");
int k;
for (k = 1; k <= 40; k++)
System.out.println("Eat at Joe's friendly diner for the best lunch value");
}
}
// Java0521.java
// This program displays 40 identical lines efficiently
// with one println statement and a loop structure.
public class Java0521
{
public static void main(String args[])
{
System.out.println("\nJAVA0521.JAVA\n");
int k;
for (k = 1; k <= 40; k++)
System.out.println("Eat at Joe's friendly diner for the best lunch value");
}
} Part 1 is used to
initialize the counter
(Loop Control
Variable).
// Java0521.java
// This program displays 40 identical lines efficiently
// with one println statement and a loop structure.
public class Java0521
{
public static void main(String args[])
{
System.out.println("\nJAVA0521.JAVA\n");
int k;
for (k = 1; k <= 40; k++)
System.out.println("Eat at Joe's friendly diner for the best lunch value");
}
} Part 1 is used to
initialize the counter
(Loop Control
Variable).
Part 2 is a condition.
As long as it is true
the loop will keep
repeating.
// Java0521.java
// This program displays 40 identical lines efficiently
// with one println statement and a loop structure.
public class Java0521
{
public static void main(String args[])
{
System.out.println("\nJAVA0521.JAVA\n");
int k;
for (k = 1; k <= 40; k++)
System.out.println("Eat at Joe's friendly diner for the best lunch value");
}
} Part 1 is used to
initialize the counter
(Loop Control
Variable).
Part 2 is a condition.
As long as it is true
the loop will keep
repeating.
Part 3 indicates
what the counter
counts by. ++
means count by 1.
// Java0522.java
JAVA0522.JAVA
// This program displays consecutive numbers 1 through 15.
//
1 It2also3 shows
4 5how
6 the
7 loop
8 control
9 10 variable
11 12 may
13 be14 15
// defined inside the <for> program statement.
public class Java0522
{
public static void main(String args[])
{
System.out.println("\nJAVA0522.JAVA\n");
for (int k = 1; k <= 15; k++)
System.out.print(k + " ");
System.out.println();
}
}
Defining the Loop Control Variable
Before the loop heading (not used much)
int k;
for (k = 1; k <= 10; k++)
{
System.out.println("Hello World");
}
Inside the loop heading (preferred approach)
for (int k = 1; k <= 10; k++)
{
System.out.println("Hello World");
}
// Java0523.java
JAVA0523.JAVA
// This program demonstrates how to use block ####################################
structure
Line Number 1
// with a <for> loop control structure.
####################################
Line Number 2
####################################
Line Number 3
public class Java0523
####################################
Line Number 4
{
####################################
Line Number 5
public static void main(String args[])
####################################
Line Number 6
{
####################################
Line Number 7
System.out.println("\nJAVA0523.JAVA\n");
####################################
Line Number 8
int k;
####################################
Line Number 9
####################################
Line Number 10
for (k = 1; k <= 10; k++)
{
System.out.println("####################################");
System.out.println("Line Number " + k);
}
System.out.println();
}
}
//
Java0524.java
JAVA0524.JAVA
// This program displays various counting schemes.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
// It also demonstrates the versatility of the <for> loop.
1
4
7
10
13
public
class Java0524
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1
{
0.0 public
0.5 static
1.0 1.5
2.0 2.5 3.0
void main(String
args[])
A B{ C D E F G H I J K L M N O P Q R S T U V W X Y Z
System.out.println("\nJAVA0524.JAVA\n");
for (int p = 1; p <= 15; p++)
System.out.print(p + " ");
You do NOT always have to use
System.out.println("\n");
++ in the 3rd part of a for loop.
for (int q = 1; q <= 15; q+=3)
System.out.print(q + " ");
You can count by any amount.
System.out.println("\n");
for (int r = 15; r >= 1; r--)
System.out.print(r + " ");
You can count backwards.
System.out.println("\n");
for (double s = 0; s <= 3; s+=0.5)
System.out.print(s + " ");
You can count by fractional
System.out.println("\n");
amounts.
for (char t = 'A'; t <= 'Z'; t++)
System.out.print(t + " ");
You can even count with
System.out.println("\n\n");
}
characters.
}
Fixed Repetition
Java has a variety of control structures for repetition.
Other computer science terms for repetition are looping and iteration.
Fixed Iteration is done with the for loop structure.
General Syntax:
for (Part1; Part2; Part3)
loop body;
The for loop has three distinct parts:
Part1 initializes the Loop Control Variable.
Part2 sets the exit condition for the loop.
Part3 determines how the LCV changes.
Specific Example:
for (k = 1; k <= 10; k++)
System.out.println("Java is 10 times more fun");
Conditional Repetition
Real Life Examples
JAVA0525.JAVA
// Java0525.java
// This program is supposed to keep repeating until a correct PIN# of 5678 is entered.
Enteris4 used
digit PIN.
1234
// The program does not work because the <for> loop
in an-->inappropriate
manner.
// The <for> loop is meant for "fixed" repetition. That is not the correct PIN. Try Again.
// Entering a PIN# is an example of "conditional" repetition.
Enter 4 digit PIN. --> 2345
public class Java0525
That is not the correct PIN. Try Again.
{
Enter 4 digit PIN. --> 3456
public static void main(String args[])
{
That is not the correct PIN. Try Again.
System.out.println("\nJAVA0525.JAVA\n");
Enter 4 digit PIN. --> 4567
for (int j = 1; j <= 10; j++)
That is not the correct PIN. Try Again.
{
Enter 4 digit PIN. --> 5678
System.out.println();
Enter 4PIN#.
digit PIN. -->
--> 5678
System.out.print("Enter 4 digit
");
int pin = Expo.enterInt(); Enter 4 digit PIN. --> 5678
if (pin != 5678)
Enter 4 digit PIN. --> 5678
System.out.println("That is not
the correct PIN. Try Again.");
Enter 4 digit PIN. --> 5678
}
Enter 4 digit PIN. --> 0000
System.out.println("\nYou are now logged in. Welcome to the program.");
}
}
That is not the correct PIN. Try Again.
You are now logged in. Welcome to the program.
JAVA0526.JAVA
// Java0526.java
// This program fixes the problem of the previous program by using a while command.
PIN. --> 1234
// Now the loop will stop when the correct PIN# of Enter
5678 4isdigit
entered.
That is not the correct PIN. Try Again.
public class Java0526
Enter 4 digit PIN. --> 2345
{
public static void main(String args[])
That is not the correct PIN. Try Again.
{
Enter 4 digit PIN. --> 3456
System.out.println("\nJAVA0526.JAVA\n");
int pin = 0;
That is not the correct PIN. Try Again.
Enter 4 digit PIN. --> 4567
while (pin != 5678)
That is not the correct PIN. Try Again.
{
Enter 4 digit PIN. --> 5678
System.out.println();
are nowPIN#.
logged in. Welcome
System.out.print("Enter 4You
digit
--> ");to the program.
pin = Expo.enterInt();
if (pin != 5678)
}
System.out.println(“That is not the correct PIN. Try Again.");
System.out.println("\nYou are now logged in. Welcome to the program.");
}
}
// Java0527.java
// This program removes the keyboard input and instead generates
// random 4-digit numbers until it is granted access.
public class Java0527
{
public static void main(String args[])
{
System.out.println("\nJAVA0527.JAVA\n");
int randomValue = 0;
while (randomValue != 5678)
{
randomValue = Expo.random(1000,9999);
System.out.print(randomValue + " ");
}
System.out.println("\n\n");
}
}
Java0527.java Output
The output may go on for several seconds…
JAVA0527.JAVA
1666
3008
7042
1893
6421
9526
5382
7496
2699
2058
7617
6891
7319
3686
6950
6459
2149
6628
2719
5939
3539
4915
9914
2370
9808
7126
8482
6248
9386
3366
1153
6266
3113
6779
8070
6094
6373
4617
5644
2728
8055
5389
7109
8389
9644
7869
8526
4950
7399
9539
3266
9091
2184
8462
4930
2348
8660
3624
1431
5678
1325
6142
6819
4836
8262
9406
3952
5356
7056
3238
5810
7830
2943
1840
2884
6795
2035
1732
3986
7170
8310
6828
5186
9423
2740
2081
4166
1571
7061
4750
1411
4040
3152
2983
5297
8291
5881
5552
2439
3473
1370
4232
5840
5603
5117
9702
3262
8197
3682
7749
3066
3245
2250
2880
4205
4923
5333
6078
9605
5234
9744
5275
3737
9888
1182
4087
5694
6914
1853
9601
8531
1536
6384
2101
4637
9771
7848
5569
9402
7614
8142
4592
4077
3052
8236
1826
6560
6448
5392
8392
6628
3881
9382
8391
3240
6814
4276
3848
6742
3691
1969
9210
7312
1931
3881
7038
3602
5372
4244
5506
6482
7359
2608
4759
6484
7156
5219
5666
1487
7495
4889
5974
3487
3271
7498
1475
8626
1196
7860
2686
9572
3241
5370
7485
5513
4364
7414
9337
8525
3050
7286
9218
7682
2017
6749
8477
1702
8162
4905
1294
9701
5461
6737
6065
3506
4588
7586
3661
7490
2519
6939
5147
1679
4926
7115
5912
9647
2940
6593
7777
8926
1898
3027
5443
4816
4263
8277
7441
4392
6777
8590
3699
8064
1772
4280
9079
2744
8750
7102
5042
… but it will eventually stop at 5678.
9823
6741
9991
4327
4332
8240
3269
3861
2764
2517
7012
2731
5717
6712
3108
3734
7537
7124
1898
Flags
The flag is the special value that makes the loop stop.
Maybe this value is entered by the user.
Maybe it is computed in the loop.
Whatever special value makes the loop stop is the flag.
A good way to remember that is
to think of a race track.
Cars go in a loop again and again.
The race keeps going until the
checkered flag is waved and the
race is over.
Conditional Repetition
General Syntax:
initialize condition variable before the while loop
while(condition is true)
{
loop body
alter condition variable in the loop body
}
Specific Example:
int pin = 0;
// initialize condition variable
while(pin != 5678)
{
System.out.print("Enter pin. ===>> ");
pin = Expo.enterInt();
// alter condition variable
}
System.out.println("Welcome.");
Program Segment
NoNo #1
Program Segment
YesYes #1
int x = 0;
while(x < 10)
System.out.println(x);
int x = 0;
while(x < 10)
{
x++;
System.out.println(x);
}
The loop condition variable,
x, never changes. The loop
will not exit.
The loop condition variable,
x, changes. The loop exits
when x reaches 10.
Program Segment
NoNo #2
Program Segment
YesYes #2
int x;
while(x < 10)
{
x++;
System.out.println(x);
}
int x = 0;
while(x < 10)
{
x++;
System.out.println(x);
}
The loop condition
variable, x, is never
initialized. This program
will not compile in Java.
The loop condition
variable, x, is initialized.
The program will compile
and execute normally.
Fixed Repetition vs.
Conditional Repetition
Fixed Repetition describes a situation where you know – ahead
of time – how many times you want the loop to repeat.
An example would be drawing exactly 100 circles on the screen.
The command for fixed repetition is for.
Conditional Repetition describes a situation where you do NOT
know how many times the loop will repeat.
The loop has to repeat until some condition is met.
An example would be entering a password.
The command for conditional repetition is while.
// Java0528.java
// This program demonstrates that <for> loopJAVA0528.JAVA
structures
// can be nested. It will display HELLO WORLD 6 times.
HELLO
public class Java0528
HELLO
{
HELLO
public static void main(String args[])
{
HELLO
System.out.println("\nJAVA0528.JAVA\n");
HELLO
for (int p = 1; p <= 3; p++)
HELLO
{
for (int q = 1; q <= 2; q++)
{
System.out.println("HELLO WORLD");
}
}
System.out.println("\n\n");
}
}
WORLD
WORLD
WORLD
WORLD
WORLD
WORLD
// Java0529.java
JAVA0529.JAVA
// This program displays the values of the two
OuterLCV
loop values.
control
variable is 1
Inner loop control variable is 1
public class Java0529
Inner loop control variable is 2
{
Outer loop control variable is 2
public static void main(String args[])
Inner loop control variable is 1
{
Inner loop control variable is 2
System.out.println("\nJAVA0529.JAVA\n");
for (int p = 1; p <= 3; p++) Outer loop control variable is 3
{
Inner loop control variable is 1
System.out.println("Outer loopInner
control
is " + p);
loop variable
control variable
is 2
System.out.println();
for (int q = 1; q <= 2; q++)
{
System.out.println("Inner loop control variable is " + q);
System.out.println();
}
}
System.out.println("\n\n");
}
}
// Java0530.java
JAVA0530.JAVA
// This program displays a multiplication table with 10 rows and 15 columns.
2 3 the
4 5 columns
6 7 8 9 10
13 up
14 perfectly.
15
// Do not worry about the fact1that
do 11
not12line
2 4 6 8 10 12 14 16 18 20 22 24 26 28 30
// You will learn how to do that3 in
chapter.
6 9another
12 15 18
21 24 27 30 33 36 39 42 45
4 8 12 16 20 24 28 32 36 40 44 48 52 56 60
5 10 15 20 25 30 35 40 45 50 55 60 65 70 75
public class Java0530
6 12 18 24 30 36 42 48 54 60 66 72 78 84 90
{
7 14 21 28 35 42 49 56 63 70 77 84 91 98 105
8 16 24
32 40 48 56 64 72 80 88 96 104 112 120
public static void main(String
args[])
9 18 27 36 45 54 63 72 81 90 99 108 117 126 135
{
10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
System.out.println("\nJAVA0530.JAVA\n");
for (int r = 1; r <= 10; r++)
{
for (int c = 1; c <= 15; c++)
{
int product = r * c;
System.out.print(product + " ");
}
System.out.println();
}
System.out.println("\n\n");
}
}
// Java0531.java
JAVA0531.JAVA
// This program displays 3 multiplication tables.
// Each of the multiplication tables displays a 5 10 15 20 25
// random table value is the [2,10] range.
30 35 40 45 50
2 4 6 8 10 12 14 16 18 20
public class Java0531
6 12 18 24 30 36 42 48 54 60
{
public static void main(String args[])
{
JAVA0531.JAVA
System.out.println("\nJAVA0531.JAVA\n");
for (int p = 1; p <= 3; p++)
3 6 9 12 15 18 21 24 27 30
{
int table = Expo.random(2,10); 9 18 27 36 45 54 63 72 81 90
for (int q = 1; q <= 10; q++)
4 8 12 16 20 24 28 32 36 40
{
int product = q * table;
System.out.print(product + " JAVA0531.JAVA
");
}
8 16 24 32 40 48 56 64 72 80
System.out.println("\n\n");
}
10 20 30 40 50 60 70 80 90 100
System.out.println("\n\n");
}
8 16 24 32 40 48 56 64 72 80
}
// Java0532.java
// This program demonstrates nesting an <if> structure inside a <for> loop.
// The previous SAT program is nested in a loop that will repeat 5 times.
public class Java0532
{
public static void main (String args[])
{
System.out.println("\nJAVA0532JAVA\n");
for (int k = 1; k <= 5; k++)
{
System.out.print("Enter SAT ===>> ");
int sat = Expo.enterInt();
System.out.println();
if (sat >= 1100)
{
System.out.println("You are admitted");
System.out.println("Orientation will start in June");
}
else
{
System.out.println("You are not admitted");
System.out.println("Please try again when your SAT improves.");
}
}
}
}
System.out.println();
JAVA0532.JAVA
Enter SAT
===>>
900
You are not admitted
Please try again when your SAT improves.
Enter SAT
===>>
1000
You are not admitted
Please try again when your SAT improves.
Enter SAT
===>>
1099
You are not admitted
Please try again when your SAT improves.
Enter SAT
===>>
1100
You are admitted
Orientation will start in June
Enter SAT
===>>
1200
You are admitted
Orientation will start in June
// Java0533.java
// This program demonstrates nesting an <if> structure inside a <do...while> loop.
// The user will be asked if he/she wishes to interview another student. A response of 'Y'
// will make the program repeat. Any other response will make the program terminate.
public class Java0533
{
public static void main (String args[])
{
System.out.println("\nJAVA0533.JAVA\n");
char response;
do
{
System.out.print("Enter SAT ===>> ");
int sat = Expo.enterInt();
System.out.println();
if (sat >= 1100)
{
System.out.println("You are admitted");
System.out.println("Orientation will start in June");
}
else
{
System.out.println("You are not admitted");
System.out.println("Please try again when your SAT improves.");
}
System.out.println();
System.out.print("Do you want to interview another student? {Y/N} ===>> ");
response = Expo.enterChar();
System.out.println();
}
while (response == 'Y'); // Note: Only capital 'Y' will make the program repeat.
}
}
JAVA0533.JAVA
Enter SAT
===>>
900
You are not admitted
Please try again when your SAT improves.
Do you want to interview another student?
Enter SAT
===>>
{Y/N}
===>>
Y
{Y/N}
===>>
Y
{Y/N}
===>>
Y
{Y/N}
===>>
N
1000
You are not admitted
Please try again when your SAT improves.
Do you want to interview another student?
Enter SAT
===>>
1100
You are admitted
Orientation will start in June
Do you want to interview another student?
Enter SAT
===>>
1200
You are admitted
Orientation will start in June
Do you want to interview another student?
// Java0534.java
// This program demonstrates nesting an <if> structure inside another <if> structure.
// This will determine if a student is eligible for financial aid.
// Note that this is not an issue for students whose SAT scores are below 1100.
System.out.print("Enter SAT ===>> ");
int sat = Expo.enterInt();
if (sat >= 1100)
{
System.out.println("You are admitted");
System.out.println("Orientation will start in June");
System.out.println();
System.out.print("What is your family income? ===>> ");
double income = Expo.enterDouble();
if (income <= 20000)
{
System.out.println("You qualify for financial aid.");
}
else
{
System.out.println("You do not qualify for financial aid.");
}
}
else
{
System.out.println("You are not admitted");
System.out.println("Please try again when your SAT improves.");
}
JAVA0534.JAVA
Enter SAT
===>>
1350
You are admitted
Orientation will start in June
What is your family income?
===>>
18000
You qualify for financial aid.
JAVA0534.JAVA
Enter SAT
JAVA0534.JAVA
Enter SAT
===>>
1500
===>>
You are not admitted
Please try again when your SAT improves.
You are admitted
Orientation will start in June
What is your family income?
700
===>>
90000
You do not qualify for financial aid.
// Java0535.java
// This program demonstrates nesting <for> loops inside an <if> structure.
// The program also shows how to determine is a number is even or odd.
System.out.println("\nJAVA0708.JAVA\n");
System.out.print("Enter an integer ===>> ");
int number = Expo.enterInt();
System.out.println();
if (number % 2 == 0) // if the number is even
{
for (int k = 1; k <= 256; k++)
{
System.out.print("EVEN ");
}
}
else // if the number is odd
{
for (int k = 1; k <= 256; k++)
{
System.out.print("ODD ");
}
}
JAVA0535.JAVA
Enter an integer
ODD ODD ODD
ODD ODD ODD
ODD ODD ODD
ODD ODD ODD
ODD ODD ODD
ODD ODD ODD
ODD ODD ODD
ODD ODD ODD
ODD ODD ODD
ODD ODD ODD
ODD ODD ODD
ODD ODD ODD
ODD ODD ODD
ODD ODD ODD
ODD ODD ODD
ODD ODD ODD
JAVA0535.JAVA
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
Enter an integer
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
===>>
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
===>>
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
1
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
2
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
// Java0536.java
// This program nests the previous program inside a <for> loop.
// Now we have <for> loops nested inside an <if> structure nested
// inside another <for> loop.
for (int j = 1; j <= 5; j++)
{
if ( j % 2 == 0) // if the loop counter is even
{
for (int k = 1; k <= 64; k++)
{
System.out.print("EVEN ");
}
}
else // if the loop counter is odd
{
for (int k = 1; k <= 64; k++)
{
}
}
}
System.out.print("ODD ");
JAVA0536.JAVA
j = 1
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
j = 2
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
j = 3
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
j = 4
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
EVEN
j = 5
ODD
ODD
ODD
ODD
ODD
ODD
ODD
ODD
// Java0537.java
// This program shows how a control structure can be used with graphics.
// This program draws vertical lines, because the starting x and
// ending x values are the same.
import java.awt.*;
import java.applet.*;
public class Java0537 extends Applet
{
public void paint(Graphics g)
{
int x1 = 100;
int y1 = 100;
int x2 = 100;
int y2 = 500;
for (int k = 1; k <= 81; k++)
{
Expo.drawLine(g,x1,y1,x2,y2);
x1 += 10;
x2 += 10;
}
}
}
// Java0538.java
// This program shows how a control structure can be used with graphics.
// This program draws horizontal lines, because the starting y and
// ending y values are the same.
import java.awt.*;
import java.applet.*;
public class Java0538 extends Applet
{
public void paint(Graphics g)
{
int x1 = 100;
int y1 = 50;
int x2 = 900;
int y2 = 50;
for (int k = 1; k <= 50; k++)
{
Expo.drawLine(g,x1,y1,x2,y2);
y1 += 10;
y2 += 10;
}
}
}
// Java0539.java
// This program shows how a control structure can be used with graphics.
// This program draws parallel diagonal lines and changes all 4 variables.
import java.awt.*;
import java.applet.*;
public class Java0539 extends Applet
{
public void paint(Graphics g)
{
int x1 = 50;
int y1 = 50;
int x2 = 200;
int y2 = 300;
for (int k = 1; k <= 60; k++)
{
Expo.drawLine(g,x1,y1,x2,y2);
x1 += 10;
x2 += 10;
y1 += 5;
y2 += 5;
}
}
}
// Java0540.java
// This program demonstrates several lines with the same starting point.
// In this case the (x1,y1) coordinate stays fixed and the (x2,y2) point changes.
import java.awt.*;
import java.applet.*;
public class Java0540 extends Applet
{
public void paint(Graphics g)
{
int x1 = 50;
int y1 = 50;
int x2 = 900;
int y2 = 50;
for (int k = 1; k <= 50; k++)
{
Expo.drawLine(g,x1,y1,x2,y2);
y2 += 10;
x2 -= 15;
}
}
}
// Java0541.java
// This program demonstrates several ovals.
// All of the ovals have the same center and vertical radius.
// The horizontal radius keeps changing.
import java.awt.*;
import java.applet.*;
public class Java0541 extends Applet
{
public void paint(Graphics g)
{
int x = 500;
int y = 325;
int hr = 50;
int vr = 100;
for (int k = 1; k <= 40; k++)
{
Expo.drawOval(g,x,y,hr,vr);
hr += 10;
}
}
}