#include<stdio.h>
#include<string.h>


long long int count,wordnumber,i,j,N;
char c,c2='/0';

char cond(char c)
{
if(int(c)>=65&&int(c)<=90||int(c)>=97&&int(c)<=122) return 1;
else return 0;
}


int main()
{

FILE*in=fopen("text.in","r");
FILE*out=fopen("text.out","w");
while(!feof(in))
{

  fscanf(in,"%c",&c);
  if(cond(c)) count++;
   else if(cond(c2)) wordnumber++;
  c2=c;
}
if(cond(c2)) wordnumber++;
fprintf(out,"%lld",count/wordnumber);

fcloseall();
return 0;
}