题解在此

#include <bits/stdc++.h>
using namespace std;
int main() {
    int n;
    cin>>n;
    int cnt=0;
    string s;
    while (n){
        s.push_back((n%2)+'0');
        n/=2;
    }
    reverse(s.begin(),s.end());
    cout<<s;
    return 0;
}