string秒了

#include <bits/stdc++.h>
using namespace std;
int main(){
    string a,ans;
    cin >> a;
    if(a[0]=='-') cout << '-';
    for(int i=a.size()-1;i>=0;i--){
        if(a[0]=='-' and i==0) break;
        if(ans.size()==0 and a[i]=='0') continue;
        ans+=a[i];
    }
    cout << ans;
    return 0;
}