Print all Combination by Backtracking

#include<bits/stdc++.h>

using namespace std;

int number[101], n, r;

void combination(int pos, int last)

{

    if(pos == r+1)

    {

        for(int i=1; i<=r; i++)

            cout << number[i] << " ";

        cout << "\n";

        return;

    }

    for(int i=last+1; i<=n-r+pos; i++)

    {

        number[pos] = i;

        combination(pos+1, i);

    }

}

int main()

{

    cout << "Enter n and r :: ";

    cin >> n >> r;

    cout << "Combinations are :: \n";

    combination(1, 0);

    return 0;

}