Selection Sorting using Recursion – Algorithms & Data Structures in C++

-// Recursive C++ program to sort an array

// using selection sort

#include <iostream>

using namespace std;

 

// Return minimum index

int minIndex(int a[], int i, int j)

{

if (i == j)

return i;

 

// Find minimum of remaining elements

int k = minIndex(a, i + 1, j);

 

// Return minimum of current and remaining.

return (a[i] < a[k])? i : k;

}

 

// Recursive selection sort. n is size of a[] and index

// is index of starting element.

void recurSelectionSort(int a[], int n, int index = 0)

{

// Return when starting and size are same

if (index == n)

return;

 

// calling minimum index function for minimum index

int k = minIndex(a, index, n-1);

 

// Swapping when index nd minimum index are not same

if (k != index)

swap(a[k], a[index]);

 

// Recursively calling selection sort function

recurSelectionSort(a, n, index + 1);

}

 

// Driver code

int main()

{

int arr[] = {3, 1, 5, 2, 7, 0};

int n = sizeof(arr)/sizeof(arr[0]);

 

// Calling function

recurSelectionSort(arr, n);

 

//printing sorted array

for (int i = 0; i<n ; i++)

cout << arr[i] << ” “;

cout << endl;

return 0;

}