insertion sort algorithm code example

Example 1: insertion sort python

def insertionSort(alist):

   for i in range(1,len(alist)):

       #element to be compared
       current = alist[i]

       #comparing the current element with the sorted portion and swapping
       while i>0 and alist[i-1]>current:
           alist[i] = alist[i-1]
           i = i-1
          alist[i] = current

       #print(alist)

   return alist

print(insertionSort([5,2,1,9,0,4,6]))

Example 2: java insertion sort

/**
* Insertion sort algorithm, O(n^2) time complexity.
*/
public static void insertionSort(int[] arr) {
  int n = arr.length;
  for(int i = 1; i < n; i++) {
    int key = arr[i];
    int j = i - 1;
    //shift until you find the position to place the element 'key'
    while(j >= 0 && arr[j] > key) {
      arr[j+1] = arr[j];
      j--;
    }
    //place element 'key' in the correct position in the sorted part of the array
    arr[j+1] = key;
  }
}

Example 3: insertion sort python

def insertion_sort(lst):
    for i in range(1,len(lst)):
        while i > 0 and lst[i - 1] >lst[i] :
            lst[i - 1], lst[i] = lst[i] , lst[i - 1]
            ## swapping
            i = i -1
    return lst
print(insertion_sort([4,2,2,3,4,3,1,1,1,2]))

Example 4: insertion sort java

Insertion program
public class InsertionSortExample
{
   public void sort(int[] arrNum)
   {
      int number = arrNum.length;
      for(int a = 1; a < number; ++a)
      {
         int keyValue = arrNum[a];
         int b = a - 1;
         while(b >= 0 && arrNum[b] > keyValue)
         {
            arrNum[b + 1] = arrNum[b];
            b = b - 1;
         }
         arrNum[b + 1] = keyValue;
      }
   }
   static void displayArray(int[] arrNum)
   {
      int num = arrNum.length;
      for(int a = 0; a < num; ++a)
      {
         System.out.print(arrNum[a] + " ");
      }
      System.out.println();
   }
   public static void main(String[] args)
   {
      int[] arrInput = { 50, 80, 10, 30, 90, 60 };
      InsertionSortExample obj = new InsertionSortExample();
      obj.sort(arrInput);
      displayArray(arrInput);
   }
}

Example 5: insertion sort

def insertionSort(arr): 
    for i in range(1, len(arr)): 
        key = arr[i] 
        j = i-1
        while j >= 0 and key < arr[j] : 
                arr[j + 1] = arr[j] 
                j -= 1
        arr[j + 1] = key

Example 6: Insertion sort algorithm

INSERTION-SORT(A)
   for i = 1 to n
   	key ← A [i]
    	j ← i – 1
  	 while j > = 0 and A[j] > key
   		A[j+1] ← A[j]
   		j ← j – 1
   	End while 
   	A[j+1] ← key
  End for