Selection Sort

Overview

Selection sort is the most basic way of sorting an Array. We compare each element with its subsequent elements and swap them if one is smaller than the other.

Complexity

The complexity of selection sort algorithm for worst case, average cases and best cases is O(n²).

Selection Sort in Java

package com.techstackjournal;

public class SelectionSort {

	public static void main(String[] args) {

		int[] nums = { 10, 4, 9, 3, 1, 5, 8, 2, 7 };
		int temp;

		for (int i = 0; i < nums.length - 1; i++) {
			for (int j = i + 1; j < nums.length; j++) {
				if (nums[i] > nums[j]) {
					temp = nums[i];
					nums[i] = nums[j];
					nums[j] = temp;
				}
			}
		}

		for (int i : nums) {
			System.out.print(i + " ");
		}

	}

}

Selection Sort in C language

#include <stdio.h>

void sort(int *nums, int len) {
	int temp;

	for (int i = 0; i < 9; i++) {
		for (int j = i + 1; j < 10; j++) {
			if (nums[i] > nums[j]) {
				temp = nums[i];
				nums[i] = nums[j];
				nums[j] = temp;
			}
		}
	}
}

int main() {

	int nums[] = { 10, 4, 9, 3, 1, 5, 8, 2, 7, 6 };

	printf("Unsorted array:\n");
	for (int i = 0; i < 10; i++) {
		printf("%d ", nums[i]);
	}

	printf("\n\nSorted array:\n");
	sort(nums, 10);

	for (int i = 0; i < 10; i++) {
		printf("%d ", nums[i]);
	}

	return 0;
}

Selection Sort in C++

#include <iostream>

using namespace std;

void sort(int *nums, int len)
{
    int temp;

    for (int i = 0; i < 9; i++)
    {
        for (int j = i + 1; j < 10; j++)
        {
            if (nums[i] > nums[j])
            {
                temp = nums[i];
                nums[i] = nums[j];
                nums[j] = temp;
            }
        }
    }
}

int main()
{

    int nums[] = { 10, 4, 9, 3, 1, 5, 8, 2, 7, 6 };

    cout<<"Unsorted array:\n";
    for (int i = 0; i < 10; i++)
    {
        cout<<nums[i]<<" ";
    }

    cout<<"\n\nSorted array:\n";
    sort(nums, 10);

    for (int i = 0; i < 10; i++)
    {
        cout<<nums[i]<<" ";
    }

    return 0;
}