#39565: python sum函數大推
pop 將list[0]提取出，sum計算list內所有元素的合，接著按題意判斷跟輸出
while True:
try:
numbers=list(map(int,input().split()))
a=numbers.pop(0)
if sum(numbers)/a>59:
print('no')
else:
print('yes')
except:
break