#include <bits/stdc++.h>

using namespace std;

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

int main()
{
    int sol = 0 , ct=0 , nr=0 ;
    char ch;
    while ( fin.get(ch) )
    {
        if ( (ch >= 'a' && ch <= 'z' )||(ch >= 'A' && ch <= 'Z' ) )
        {
            ct++ ;
            if ( ct == 1 )
                nr++ ;
        }
        else
        {
            sol = sol + ct ;
            ct = 0 ;
        }
    }
    fout << sol/nr ;
}