-Algorithm for insertion sort (#284)

Java/InsertionSort.java

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+/*INSERTION SORT-->
+-> Insertion sort is a simple sorting algorithm that works by building a sorted array one element at a time.
+It is considered an ” in-place ” sorting algorithm, meaning it doesn’t require any additional memory space beyond the original array.
+
+-> The array is virtually split into a sorted and an unsorted part. Values from the unsorted part are picked
+and placed at the correct position in the sorted part.
+  
+* ALGORITHM -->
+1) Input :- An array of integers.
+
+2) We will take an outer loop, which iterate from zeroth index of an array to (length of array - 1)th index.
+    :)This loop select an element in each iteration from the unsorted array.
+    :)The first element of the array is assumed to be sorted.
+
+3) For each element, compare it with the elements before it(or compare it with sorted sub-array) by using inner loop.
+    :)Shift all the elements in sorted sub-array that is greater than the value to be sorted using swapping function inside inner loop.
+    :)Insert current element into it's correct position.
+
+4) Output -> Sorted array in ascending order.
+
+Time complexity -> Best Case=O(n):when the array is already sorted.
+Average and Worst Case = O(n^2):due nested loops
+*/
+
+class InsertionSort{
+    static void insertionSort(int[] arr,int n){
+        for(int i=0;i<n;i++){
+            int j=i;
+            while(j>0 && arr[j-1]>arr[j]){
+                int temp=arr[j-1];
+                arr[j-1]=arr[j];
+                arr[j]=temp;
+                j--;
+            }
+        }
+
+    }public static void main(String [] args){
+        int[] arr={7,9,24,27,2,15};
+        int n=arr.length;
+        insertionSort(arr,n);
+        System.out.println("After insertion sort");
+        for(int i=0;i<n;i++){
+            System.out.print(arr[i]+" ");
+
+        }
+    }
+}