c++ loop programs

#include <iostream>
using namespace std;

int main() {
    // Program 1: Simple for loop
    for (int i = 0; i < 5; ++i) {
        cout << i << " ";
    }
    cout << endl;

    // Program 2: Nested for loop
    for (int i = 0; i < 3; ++i) {
        for (int j = 0; j < 4; ++j) {
            cout << i << "," << j << " ";
        }
        cout << endl;
    }

    // Program 3: While loop
    int counter = 0;
    while (counter < 3) {
        cout << counter << " ";
        ++counter;
    }
    cout << endl;

    // Program 4: Do-while loop
    int num = 0;
    do {
        cout << num << " ";
        ++num;
    } while (num < 4);
    cout << endl;

    return 0;
}