#include <iostream>
#include <fstream>
#include <cstring>
using namespace std;
char a[1000];
int main()
{
    int i,j,l=0,c=0;
    ifstream f("text.in");
    ofstream g("text.out");
    f.getline(a,1000,'\n');
    i=strlen(a);
    for(j=1;j<=i;j++)
        if((a[j]>='a' && a[j]<='z') || (a[j]>='A' && a[j]<='Z'))l++;
           else if((isalpha(a[j-1]) && isalpha(a[j+1])) || a[j]==',')c++;
    g<<l/(c+1);
    }