#include <bits/stdc++.h>
using namespace std;
#define i64 long long
#define rep(i,s,e) for(int (i) = (s);(i) <= (e);(i)++)
string b;
string s;
int main(){
    i64 m = 1e9 + 7;
    b = to_string(m);
    cin >> s;
    cout << abs((int)s.size() - (int)b.size()) << endl;
}