#include<stdio.h>
FILE *f=fopen("text.in","r"),*g=fopen("text.out","w");
char b[1000],a;
int main()
{
int j=0,i=0,ok=0,lm=0,cv=0;
fgets(b,999,f);
if(b[0]!=' '||b[0]!='-'||b[0]!=',')i=1;
for(;;)
{
 j++;
 a=b[j];
 ok=0;
 if(a=='\x0')ok=1;
 if(a==' ')ok=1;
 if(a=='-')ok=1;
 if(a==',')ok=1;
 if(ok==0)i++;
 if(ok==1)
 {
  if(i>0){lm=lm+i;cv++;i=0;}
 }
 if(a=='\x0')break;
}
fprintf(g,"%d",lm/cv);
return 0;
}