#include<fstream>
#include<string.h>
using namespace std;
int main()
{
    fstream f,g;
    f.open("text.in",ios::in);
    g.open("text.out",ios::out);
    char s[1000000],*p;
    int i,nr=0,nr1=0,ok;
    f.getline(s,1000);
    p=strtok(s," 1234567890!~`!@#$%^&*()-+=/?><.,_-");
    while(p!=NULL)
    {
        nr=nr+strlen(p);
        p=strtok(NULL," 1234567890!~`!@#$%^&*()-+=/?><.,_-");
        nr1++;
    }
    g<<nr/nr1;

    /*i=0;
    nr=0;
    nr1=0;
    while(i<strlen(s))
    {
        while((s[i]>='a' && s[i]<='z') || (s[i]>='A' && s[i]<='Z'))
        {
            i++;
            nr++;
            if(ok==0)
            {
                ok=1;
                nr1++;
            }
        }
        while((s[i]<'a' || s[i]>'z') && (s[i]<'A' || s[i]>'Z'))
            i++;
        ok=0;
    }
    g<<nr/nr1;*/
}