#include<bits/stdc++.h>

using namespace std;

int main(){

int N;

int v;

while(cin >> N){

int sum = 0;

int arr[N];

for(int i = 0; i < N; i++){

cin >> v;

arr[i] = v;

}

for(int i = 0; i < N; i++){

sum += arr[i];

}

int avg = sum / N;

if(avg > 59){

cout << "no" << endl;

}else{

cout << "yes" << endl;

}

}

}

除法要注意轉換成整數的問題，或著浮點誤差

這題建議不要用除法，改成用乘法計算再做比較