Download Insertion-Sort

Insertion Sort is an efficient algorithm for sorting a small number of elements. It is similar to sort a
hand of playing cards.
Playing a card is one of the techniques of sorting and in Insertion Sort we follow following steps.
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Start with an empty left hand and cards face down on the table.
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Then remove one card at a time from the table and Insert it into the correct position in
the left hand.
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To find a correct position for a card, we compare it with each of the cards already in the
hand from right to left.
Input : A sequence of n numbers a1, a2, ..., an.
Output : A permutation (reordering) of the input sequence such that a1<=a2<=a3<=….an
The numbers that we wish to sort are also known as Keys. Although conceptually we are sorting a
sequence, then input comes to us in the form of an array with n elements.
Pseudocode of Insertion Sort
INSERTION-SORT(A)
1. for j = 2 to n
2.
key ← A [j]
3.
// Insert A[j] into the sorted sequence A[1..j-1]
4.
j←i–1
5.
while i > 0 and A[i] > key
6.
A[i+1] ← A[i]
7.
i←i–1
8.
A[j+1] ← key