Given an integer N, find its binary representation.

bin_rep.cpp

#include <iostream>
#include <string>
using namespace std;

#define ull uint64_t

string bin_rep(ull n) {
    if (n == 0) return "";
    string rem(1, (n&1) + '0'); // https://www.geeksforgeeks.org/how-to-convert-a-single-character-to-string-in-cpp/
    return bin_rep(n>>=1) + rem;
}

int main() {
    int t;  cin >> t;
    while(t--) {
        ull n;  cin >> n;
        string ans = (n == 0) ? "0" : bin_rep(n);
        cout << ans << "\n";
    }
    return 0;
}