就会女vvvvvvvvvvvvvvv搞不好店内顾客是v任何时刻挂念二哥发韵达关于v你电话v不拿出那个荣誉通过

include <bits/stdc++.h>

include

using namespace std;

int main() {

string s;
cin >> s;
cout << count(s.begin(), s.end(), '1');

return 0;

}