CF1176C.Lose it!

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题目描述

You are given an array aa consisting of nn integers. Each aia_i is one of the six following numbers: 4,8,15,16,23,424, 8, 15, 16, 23, 42 .

Your task is to remove the minimum number of elements to make this array good.

An array of length kk is called good if kk is divisible by 66 and it is possible to split it into k6\frac{k}{6} subsequences 4,8,15,16,23,424, 8, 15, 16, 23, 42 .

Examples of good arrays:

  • [4,8,15,16,23,42][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][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][4, 8, 15, 16, 42, 23] (the order of elements should be exactly 4,8,15,16,23,424, 8, 15, 16, 23, 42 );
  • [4,8,15,16,23,42,4][4, 8, 15, 16, 23, 42, 4] (the length of the array is not divisible by 66 );
  • [4,8,15,16,23,42,4,8,15,16,23,23][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 nn ( 1n51051 \le n \le 5 \cdot 10^5 ) — the number of elements in aa .

The second line of the input contains nn integers a1,a2,,ana_1, a_2, \dots, a_n (each aia_i is one of the following numbers: 4,8,15,16,23,424, 8, 15, 16, 23, 42 ), where aia_i is the ii -th element of aa .

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
    
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