#include <bits/stdc++.h>

using namespace std;

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

const int NMAX=1e7;

char sir[NMAX+5];

int N, i;

long long litere, cuvinte;

int main()
{
    f.getline(sir, NMAX+1);

    N=strlen(sir);

    for(i=0; i<N; i++)
    {
        if(isalpha(sir[i]))
        {
            cuvinte++;

            while(isalpha(sir[i]))
            {
                litere++;
                i++;
            }

            i--;
        }
    }

    g<<(long long) litere/cuvinte<<'\n';

    return 0;
}