#!/usr/bin/python
# -*- coding: utf-8 -*-

N = int(raw_input())
array = map(int, raw_input().split())
sum = float(sum(array))
ans = 0

if sum == 0:
       	print 30 * len(array)
       	exit()

for i in array:
       	if i / sum <= 0.1:
       		ans += 30
print ans