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A12581 | Lose it!

时间限制1s
内存限制256MB
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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 #1
5
4 8 15 16 23
输出 #1
5
输入 #2
12
4 8 4 15 16 8 23 15 16 42 23 42
输出 #2
0
输入 #3
15
4 8 4 8 15 16 8 16 23 15 16 4 42 23 42
输出 #3
3
C++ 编辑器
输入
输出