/*
#include <iostream>
#include <cstring>
#include <fstream>

using namespace std;

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

int main()
{
    char sir[101];
    fin.getline(sir, 101);
    int n=strlen(sir);
    int cnt1=0, cnt2=0;
    for(int i=1;i<=n;i++)
        if((sir[i]>='a' && sir[i]<='z')||(sir[i]>='A' && sir[i]<='Z'))
            cnt1++;

    char sep[]=" .,!?-";
    char *p=strtok(sir, sep);
    while(p!=NULL)
    {
        cnt2++;
        p=strtok(NULL, sep);
    }
    fout<<cnt1/cnt2;

    fin.close();
    fout.close();
    return 0;
}
*/



#include <iostream>
#include <fstream>
using namespace std;

int e_litera(char a)
{
    if((a>=65 && a<=90) || (a>=97 && a<=122) )
        return 1;

        return 0;
}
int main()
{
    int nrcuvinte=0;
    int nrlitere=0;
    ifstream cit("text.in");
    char c;
    char lastChar=0;
    while(cit>> noskipws >>c)
    {

        if(e_litera(c))  nrlitere++;

        if(lastChar!=0)
        {
            if(!e_litera(c) && e_litera(lastChar))
                nrcuvinte++;
        }
        lastChar=c;


    }
    ofstream cut("text.out");
    cut<<nrlitere/nrcuvinte;
    cut.close(); cit.close();

    return 0;
}