#include <iostream>
#include <cstring>
#include <fstream>

using namespace std;

ifstream fin("text.in");
ofstream fout("text.out");

char sir[1005], *p;
long long ok=0, nr_litere=0;

int main()
{
    fin.getline(sir,1005);
    for(int i=0;i<strlen(sir);i++)
    {
        if((sir[i]>='a' && sir[i]<='z') || (sir[i]>='A' && sir[i]<='Z'))
               nr_litere++;
    }
    p=strtok(sir," ,.!:'/}?|!@#$%^&*-_+=<> ");
    while(p)
    {
        ok++;
        p=strtok(NULL," ,.!:'/}?|!@#$%^&*-_+=<> ");
    }
    nr_litere/=ok;
    fout<<nr_litere;
    return 0;
}