#include <iostream>
# include <stdio.h>
# include <stdlib.h>
using namespace std;
int main(){
 long long int a,b,n=0;
 while(cin>>b){
  for(int c=0;c<b;c++){
   cin>>a;
   n+=a;
  }
  if(n/b<=59)
   printf("yes\n");
  else
   printf("no\n");
  }
}

注意會有小數

已改成long double

還是WA求指正

n 歸 0