#include <cstdio>
#include <cstring>
#include <cctype>

using namespace std;

int n , crt , lg , nr , total;

char A[1000010];

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

    while (gets(A))
    {
        n = strlen(A);

        crt = 0;
        while (crt <= n)
        {
            lg = 0;
            while (isalpha(A[crt])) lg++ , crt++;

            if (lg == 0) crt++;
            else nr++;

            total += lg;
        }
    }

    printf("%d\n", total / nr);


    return 0;
}