#include <stdio.h>
#include <string.h>
#include <ctype.h>
char textln[300];

void nrsol(long &nrl,long &nrc)
{int i;
char *p,del[]=" ;.',/><=+-{}[]@#$%^&*()`~!?";
p=strtok(textln,del);
 while(p)
  {nrc++;
   for(i=0;i<strlen(p);i++)
    if(isalpha(p[i]))
     nrl++;
   p=strtok(0,del);
  }
}

int main()
{FILE *fin=fopen("text.in","r");
long nrl=0,nrc=0,nr;
while(!feof(fin))
 {fgets(textln,300,fin);
  if(textln[strlen(textln)-1]=='\n')
   textln[strlen(textln)-1]=NULL;
  nrsol(nrl,nrc);
 }
nr=nrl/nrc;
fclose(fin);
fin=fopen("text.out","w");
fprintf(fin,"%ld",nr);
fclose(fin);
return 0;
}