#include <iostream>
#include <fstream>
using namespace std;
ifstream f("text.in");
ofstream g("text.out");
string p;long long l,cuv,lcuv;
int main()
{
    getline(f,p);
    l=p.length();
    for(int i=1;i<l;i++){
        if(p[i]==' '&&p[i-1]!='-')
            cuv++;
        if(p[i]=='-'&&(p[i-1]>='A'&&p[i-1]<='Z'||p[i-1]>='a'&&p[i-1]<='z'))
            cuv++;}
    cuv++;
    for(int i=0;i<p.length();i++)
    {
        if(((p[i]>='A'&&p[i]<='z')||(p[i]>='a'&&p[i]<='z')))
            lcuv++;
        if(p[i]>='1'&&p[i]<='9')
            lcuv++;
    }
    g<<lcuv/cuv;
    return 0;
}