#include <stdio.h>
#include <stdlib.h>
#include <string.h>
char s[30000];
void citire(){
    int l,count=0,i,suma=0;
    char *p;
    FILE *f=fopen("text.in","r");
    FILE *g=fopen("text.out","w");
    fgets(s,30000,f);
    l=strlen(s);
    for(i=0;i<l;i++)
        if((s[i]>='a'&&s[i]<='z')||(s[i]>='A'&&s[i]<='Z'))
        count++;
    p=strtok(s," .,!:;?");
    while(p!=NULL){
        suma++;
        p=strtok(NULL," .,!:;?");
    }
    fprintf(g,"%d",count/suma);
}
int main()
{
    citire();
    return 0;
}