#include <fstream>
#include <iostream>

using namespace std;

ifstream f ("text.in");
ofstream g ("text.out");

int k, ok, nr, d, i;
char x, a[ 1000000001 ];
int main(){
    f.get( x );
    a[ 1 ] = x;
    while( x != '!' && x != '.' && x != '?' ){
        f.get( x );
        a[ ++k ] = x;
    }
    ok = 0;
    for( i = 1; i <= k; ++i ){
        if ( ( a[ i ] >= 65 && a[ i ] <= 90 ) || ( a[ i ] >= 97 && a[ i ] <= 122 ) ){
            if( ok == 0 ) nr++;
            d++;
            ok = 1;
        }
        else{
            ok = 0;
        }
    }
    g << d / nr;
}