Generate Subsets in C++

subsets.cpp

#include<iostream>
#include<vector>

using namespace std;

int print_vector(vector<int> arr){

    for(int i = 0; i < (int) arr.size(); i++){
        cout << arr[i] << " ";
    }
    cout << "\n";

    return 0;

}

int generate_subsets(vector<int> arr, int n, int k){

    if(k > n){

        print_vector(arr);
        return 0;

    } else {

        arr.push_back(k);
        generate_subsets(arr, n, k + 1);
        arr.pop_back();
        generate_subsets(arr, n, k + 1);

    }

    return 0;

}

int main(int argc, char const *argv[])
{
    
    vector<int> arr;

    generate_subsets(arr, 3, 1);

    return 0;
}