Time complexity : O(N^2)
If the key element is smaller than its predecessor, compare it to the elements before.
Move the greater elements one position up to make space for the swapped element.
// C program for insertion sort
#include <math.h>
#include <stdio.h>
/* Function to sort an array using insertion sort*/
void
insertionSort(
int
arr[],
int
n)
{
int
i, key, j;
for
(i = 1; i < n; i++) {
key = arr[i];
j = i - 1;
/* Move elements of arr[0..i-1], that are
greater than key, to one position ahead
of their current position */
while
(j >= 0 && arr[j] > key) {
arr[j + 1] = arr[j];
j = j - 1;
}
arr[j + 1] = key;
}
}
// A utility function to print an array of size n
void
printArray(
int
arr[],
int
n)
{
int
i;
for
(i = 0; i < n; i++)
printf
(
"%d "
, arr[i]);
printf
(
"\n"
);
}
/* Driver program to test insertion sort */
int
main()
{
int
arr[] = { 12, 11, 13, 5, 6 };
int
n =
sizeof
(arr) /
sizeof
(arr[0]);
insertionSort(arr, n);
printArray(arr, n);
return
0;
}