using namespace std;
#include<fstream>

FILE *f=fopen ("text.in", "r");
ofstream g ("text.out");




int main()
{
    char c,k=0;
    int nrcuv=0,nrlit=0;

    fscanf(f,"%c",&c);
    while(c!='\n')
    {

        if((c>='a' && c<='z') || (c>='A' && c<='Z'))
        {
            nrlit++;
            if(k==0) nrcuv++;
            k=-1;
        }
        else k=0;
          fscanf(f,"%c",&c);

    }

    if(!nrcuv) g<<0;
    else g<<nrlit/nrcuv;


    return 0;
}