Insertion Sort
Insertion sort is a simple sorting algorithm that works similar to the way you sort playing cards in your hands. 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.
Time Complexity:
1)The best-case time complexity of insertion sort is O(n).
2)The average case time complexity of insertion sort is O(n2).
3)The worst-case time complexity of insertion sort is O(n2).
Space Complexity:
The space complexity of insertion sort is O(1).
Java
python
JavaScript
c
// Javascript program for insertion sort
// Function to sort an array using insertion sort
function insertionSort(arr, n)
{
let 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
function printArray(arr, n)
{
let i;
for (i = 0; i < n; i++)
document.write(arr[i] + " ");
document.write("
");
}
// Driver code
let arr = [12, 11, 13, 5, 6 ];
let n = arr.length;
insertionSort(arr, n);
printArray(arr, n);
// Java program for implementation of Insertion Sort
public class InsertionSort {
/*Function to sort array using insertion sort*/
void sort(int arr[])
{
int n = arr.length;
for (int i = 1; i < n; ++i) {
int key = arr[i];
int 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 array of size n*/
static void printArray(int arr[])
{
int n = arr.length;
for (int i = 0; i < n; ++i)
System.out.print(arr[i] + " ");
System.out.println();
}
// Driver method
public static void main(String args[])
{
int arr[] = { 12, 11, 13, 5, 6 };
InsertionSort ob = new InsertionSort();
ob.sort(arr);
printArray(arr);
}
};
# Python program for implementation of Insertion Sort
# Function to do insertion sort
def insertionSort(arr):
# Traverse through 1 to len(arr)
for i in range(1, len(arr)):
key = arr[i]
# Move elements of arr[0..i-1], that are
# greater than key, to one position ahead
# of their current position
j = i-1
while j >= 0 and key < arr[j] :
arr[j + 1] = arr[j]
j -= 1
arr[j + 1] = key
# Driver code to test above
arr = [12, 11, 13, 5, 6]
insertionSort(arr)
for i in range(len(arr)):
print ("% d" % arr[i])
// C program for insertion sort
#include
#include
/* 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;
}