implementation of insertion sort in java code example

Example 1: 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 2: 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]))

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Java Example