#include<iostream>
#include<string>
#include<cmath>
using namespace std;
int main()
{
    string input;
    cin>>input;
    try{
        int number=stoi(input);
        if(number<-10000||number>10000){
    }else{
        int count=0;
        if(number==0){
            count=1;
        }else{
            int temp=abs(number);
            string s=to_string(temp);
            count=s.length();
        }
        cout<<count<<endl;
    }
    catch(const invlaid_argument&e){
        cout<<"Invalid input"<<endl;
    }catch(const out_of_range&e){
        cout<<"Invalid input"<<endl;
    }
    return 0;
}