#include <iostream>
#include <string>
#include <fstream>
using namespace std;
ifstream in("text.in");
ofstream out("text.out");
const string delim = " ,.!?|-;:";
string cuv;
inline bool find(string s,char c)
{
    for(int i=0;i<s.size();++i)
    {
        if(s[i]==c)return 1;
    }
    return 0;
}
int main()
{
    string s;
    string line;
    int cnt=0,car=0;
    whie(getline(in,line));
    {
        for(int i=0;i<line.size();++i)if(isalpha(line[i]))++car;
        for(int i=0;i<line.size();++i)
        {
            if(find(delim,line[i]))
            {
                if(cuv!="")
                {
                    ++cnt;
                    cuv="";
                }
            }
            else
            {
                cuv.push_back(line[i]);
            }
        }
        if(cuv!="")
        {
            ++cnt;
        }
    }
    out<<car/cnt;
    return 0;
}