#include<stdio.h>
#include<ctype.h>
long a,b,n,i,j;
FILE *f1,*f2;
char c;
int main(){
f1=fopen("text.in","r");
f2=fopen("text.out","w");
a=0;
while(!feof(f1)){
	fscanf(f1,"%c",&c);
	while(!isalpha(c)){
		fscanf(f1,"%c",&c);
	}
	if(!feof(f1)){
		i++;
	}
	while(isalpha(c)){
		a++;
		fscanf(f1,"%c",&c);
	}

}
fprintf(f2,"%ld",a/i);
return 0;}