#include <fstream>
#include <cstring>

using namespace std;

int lung=0, cuv=0, med, i;
char s[11000000];

ifstream fin("text.in");
ofstream fout("text.out");

int main(){
    fin.get(s, 11000000);
    for(i=0;s[i]!=0;i++){
        int x=0;
        if((s[i]>='A' && s[i]<='Z') || (s[i]>='a' && s[i]<='z'))
            while((s[i]>='A' && s[i]<='Z') || (s[i]>='a' && s[i]<='z')){
                x++;
                i++;
            }
        if(x!=0){
            lung+=x;
            cuv++;
        }
    }

    if(cuv!=0)
        med=lung/cuv;
    else
        med=0;

    fout<<med;
    return 0;
}