#include <fstream>
#include <iostream>
#include <cstring>

using namespace std;
ifstream fin ("text.in");
ofstream fout("text.out");
int main()
{
    string pilaf;
    int cnt=0,total=1,i=0;
    getline(fin,pilaf);
    //cout<<pilaf;
    while (pilaf[i++]!='\0'){
       if(pilaf[i]==' '){
        total++;
       }
       if((pilaf[i]>='A' && pilaf[i]<='Z') || (pilaf[i]>='a' && pilaf[i]<='z'))
        cnt++;
    }
    fout<<(cnt/total);
    return 0;
}