#include <fstream>
#include <cstring>
using namespace std;
ifstream in("text.in");
ofstream out("text.out");

char x[1048589];

int main()
{

    int n=0,nr=0,i;

    while(in.getline(x,1048589))

        for(i=0; x[i];)
        {
            if((x[i]>='a' && x[i]<='z') || (x[i]>='A' && x[i]<='Z'))
            {
                while ((x[i]>='a' && x[i]<='z') || (x[i]>='A' && x[i]<='Z'))
                {
                    i++;
                    n++;
                }
                nr++;
            }
            else i++;
        }
    out<<n/nr;
    return 0;
}