#include<bits/stdc++.h>
using namespace std;
int main(){
    int n;
    cin>>n;
    if(n/1000>=1){
        cout<<4;
    }else if(n/100>=1){
        cout<<3;
    }else if(n/10>=1){
        cout<<2;
    }else{
        cout<<1;
    }
    return 0;
}