Lose it!

题意翻译

你有一个长度为$n$的序列$a$，其中每一个元素都是下列6种数字中的一个：$4,8,15,16,23,42$。 你的任务是删掉最少的元素，使得这个序列变成好的。 我们称一个长度为$k$的序列是好的，当且仅当$k$能被$6$整除并且这个序列能划分成$\dfrac k6$个子序列，使得每一个子序列都是$\{4,8,15,16,23,42\}$。 下面几个序列是好的序列： $[4, 8, 15, 16, 23, 42]$（整个序列作为要求的子序列）； $[4, 8, 4, 15, 16, 8, 23, 15, 16, 42, 23, 42]$（第一个子序列由第一，二，四，五，七，十个元素构成，第二个子序列由剩下的元素构成）； $[]$（空序列是好的）. 下面几个序列是不好的序列： $[4, 8, 15, 16, 42, 23]$ $[4, 8, 15, 16, 23, 42, 4]$ $[4, 8, 15, 16, 23, 42, 4, 8, 15, 16, 23, 23]$

题目描述

You are given an array $ a $ consisting of $ n $ integers. Each $ a_i $ is one of the six following numbers: $ 4, 8, 15, 16, 23, 42 $ . Your task is to remove the minimum number of elements to make this array good. An array of length $ k $ is called good if $ k $ is divisible by $ 6 $ and it is possible to split it into $ \frac{k}{6} $ subsequences $ 4, 8, 15, 16, 23, 42 $ . Examples of good arrays: - $ [4, 8, 15, 16, 23, 42] $ (the whole array is a required sequence); - $ [4, 8, 4, 15, 16, 8, 23, 15, 16, 42, 23, 42] $ (the first sequence is formed from first, second, fourth, fifth, seventh and tenth elements and the second one is formed from remaining elements); - $ [] $ (the empty array is good). Examples of bad arrays: - $ [4, 8, 15, 16, 42, 23] $ (the order of elements should be exactly $ 4, 8, 15, 16, 23, 42 $ ); - $ [4, 8, 15, 16, 23, 42, 4] $ (the length of the array is not divisible by $ 6 $ ); - $ [4, 8, 15, 16, 23, 42, 4, 8, 15, 16, 23, 23] $ (the first sequence can be formed from first six elements but the remaining array cannot form the required sequence).

输入输出格式

输入格式

The first line of the input contains one integer $ n $ ( $ 1 \le n \le 5 \cdot 10^5 $ ) — the number of elements in $ a $ . The second line of the input contains $ n $ integers $ a_1, a_2, \dots, a_n $ (each $ a_i $ is one of the following numbers: $ 4, 8, 15, 16, 23, 42 $ ), where $ a_i $ is the $ i $ -th element of $ a $ .

输出格式

Print one integer — the minimum number of elements you have to remove to obtain a good array.

输入输出样例

输入样例 #1

5
4 8 15 16 23

输出样例 #1

5

输入样例 #2

12
4 8 4 15 16 8 23 15 16 42 23 42

输出样例 #2

0

输入样例 #3

15
4 8 4 8 15 16 8 16 23 15 16 4 42 23 42

输出样例 #3

3