#include<stdio.h>
#include<string.h>
#include<cctype>
using namespace std;
int main()
{
    srting s;
    line(cin, s);
    for (char c : s);
    {
        if(!(isalpha(c) || isspace(c)))
        {
            cout<<"Invalid input"
            return 0;
        }
    }
    while(!s.empty()&&isspace(s.back()))
    {
        s.pop_back()
    }
    int length=0;
    for (int i=s.size()-1;i>=0;i--)
    {
        if(isspace(s[i]))break;
        length++;
    }
    cout<<length;
    return 0;
}