tony 2020-10-18 0:06:08 2020-10-18 0:06:50 10 返回题目
#include<bits/stdc++.h>
using namespace std;
string s;
long long temp;
int main(){
cin>>s; for(int i=0;i<s.size();++i){ if(s[i]=='1') temp++; } cout<<temp; return 0;
}