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

long c,l;

int main()
{
freopen("text.in","r",stdin);
c=l=0;
char s[1000];
fgets(s,1000,stdin);
if(s[strlen(s)-1]=='\n') s[strlen(s)-1]=0;
char *p;
for(p=strtok(s,"`~1234567890!{@#$%^&*()-}|:+?=><,./;'[]\""); p; p=strtok(NULL,"`~1234567890!{@#$%^&**()-}|:+?=><,./;'[]\""))
     {     
      //strrev(p);
      //printf("%s\n",p);     
      ++c;
      l+=strlen(p);
     }

freopen("text.out","w",stdout);

printf("%ld",l/c);
fclose(stdin);
fclose(stdout);
return 0;
}