C++ Bubble Sort

Bubble sort is a simple sorting algorithm where we compare adjacent items and swap them if they are in the wrong order. This is repeatedly done until no exchanges are required. This article provides a sample implementation of bubble sort in C++.

Bubble Sort Introduction

• Bubble sort is a simple sorting algorithm.
• Best case time complexity is O(n) when the list is already sorted.
• Average and Worst case complexity is O(n*n). So it is not recommended for large input sets.
• Bubble sort involves these simple steps.
• Compare adjacent items and swap them if they are not in the correct order.
• Perform the above step until no exchanges are required,

Implementation of bubble sort using C++

#include <iostream>
using namespace std;

static int count = 0;
const int INPUT_SIZE = 10;

void print(int *input)
{
    for ( int i = 0; i < INPUT_SIZE; i++ )
        cout << input[i] << " ";
    cout << endl;
}

void bubblesort(int* input)
{
    count++;
    int exchanges = 0;
    for ( int i = 0; i < INPUT_SIZE; i++ )
    {
        if ( input[i] > input[i+1] )
        {
            int tmp = input[i];
            input[i] = input[i+1];
            input[i+1] = tmp;
            exchanges++;
        }
    }
    
    if ( exchanges == 0 ) return;
    cout << "Parse " << count << ":";
    print(input);
    bubblesort(input);
}

int main()
{
    int input[INPUT_SIZE] = {500, 700, 800, 100, 300, 200, 900, 400, 1000, 600};
    cout << "Input: ";
    print(input);
    bubblesort(input);
    cout << "Output: ";
    print(input);
    return 0;
}

OUTPUT:-

Input: 500 700 800 100 300 200 900 400 1000 600
Parse 1:500 700 100 300 200 800 400 900 600 1000
Parse 2:500 100 300 200 700 400 800 600 900 1000
Parse 3:100 300 200 500 400 700 600 800 900 1000
Parse 4:100 200 300 400 500 600 700 800 900 1000
Output: 100 200 300 400 500 600 700 800 900 1000