# include <algorithm>
using namespace std;

# define DIM 1 << 21

int nr_ch, nr_cuv;
char s[ DIM ];

void solve () {

    int i, lg;

    while ( gets ( s ) ) {

        lg = strlen ( s );
        for ( i = 0; i < lg; ++ i )
            if ( isalpha ( s[ i ] ) ) {

                for ( ++ nr_ch; isalpha ( s[ i + 1 ] ); ++ i, ++ nr_ch );
                ++ nr_cuv;
            }
    }
    printf ( "%d", nr_ch / nr_cuv );
}

int main () {

    freopen ( "text.in", "r", stdin );
    freopen ( "text.out", "w", stdout );

    solve ();

    return 0;
}