#include <bits/stdc++.h>
using namespace std;
#define ll long long
int main() {
     freopen("tenfile.inp","r",stdin); 
    freopen("tenfile.out","w",stdout);
    string s;
    getline(cin,s);  
    ll d=0; 
    for(char c:s) {
        if(isdigit(c)) 
            d++;
    }
    cout<<d;
    return 0;
}