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

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

int NrTotalLitere, NrLit, NrCuvinte;



#define COND_LIT(i) ( ('a'<=i && i<='z') or ('A'<=i && i<='Z') )
char x;

int main()
{
    while ( !f.eof() )
    {
        f.get(x);
        if ( COND_LIT(x) ) NrLit++; else
            if ( NrLit ) {
                NrTotalLitere += NrLit;
                NrLit = 0; NrCuvinte++;
            }
    }
    g << NrTotalLitere/NrCuvinte;
    cout<<NrTotalLitere << '/' << NrCuvinte;
}