Insertion Sort Implementation

This program sorts an array using insertion sort algorithm.

Problem Statement

Write a Java program to sort an integer array using insertion sort.

Source Code

1 public class InsertionSort {
2 public static void main(String[] args) {
3 int[] arr = {12, 11, 13, 5, 6};
4 for(int i=1; i<arr.length; i++) {
5 int key = arr[i];
6 int j = i-1;
7 while(j>=0 && arr[j] > key) {
8 arr[j+1] = arr[j];
9 j--;
10 }
11 arr[j+1] = key;
12 }
13 System.out.print("Sorted array: ");
14 for(int num : arr) System.out.print(num + " ");
15 }
16 }

Program Output

Sorted array: 5 6 11 12 13 

Explanation

The outer loop picks each element to insert, and the inner while loop shifts larger elements to the right until the key is placed at its correct position, together sorting the array in ascending order.

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