#include <stdio.h>

int main()
{
 FILE *fi = fopen("text.in", "r");
 FILE *fo = fopen("text.out", "w");
 char inWord;
 char lit;
 inWord = 0;
 long nlit = 0;
 long ncuv = 0;
 while (!feof(fi)){
       fscanf(fi, "%c", &lit);
       if (('a' <= lit && lit <= 'z') || ('A'<= lit && lit<='Z')){
                if (inWord)
                   nlit++;
                else{
                     nlit++;
                     ncuv++;
                     inWord = 1;
                }
       }
       else
           if (inWord)
              inWord = 0;
 }
 fprintf(fo, "%d", nlit/ncuv);
 fclose(fo);
 return 0;    
}