#include <stdio.h>
#include<string.h>
#include<ctype.h>
int k=0,r=0,s;
void read_solve ()
{
    int i;
    char separatori[]=" .,-!?;':";
    char *p;
    char S[255];
    gets (S);
    
     for(i=0;i<=strlen(S);i++)
    {
                             if(isalpha(S[i]))
                             r++;
    }

    
    
    
    
    p=strtok(S,separatori);
    while(p)
    {
            k++;
            p=strtok(NULL,separatori);
            }
            s=r/k;
            printf ("%ld\n",s);
            }
int main ()
{
    freopen ("text.in","r",stdin);
    freopen ("text.out","w",stdout);
    read_solve ();
    return 0;
}