#include<iostream>
using namespace std;
int main()
{
    int n;
    cin>>n;
    if(cin.fail()||n<-10000||n>10000)
    {
        cout<<"Invalid input";
    }else
    {
        n=abs(n);
        if(n==0)
        cout<<1;
        else
            cout<<(int)log10(n)+1;
    }
    return 0;
}