1042 Shuffling Machine (20 分)

1. 题目

Shuffling is a procedure used to randomize a deck of playing cards. Because standard shuffling techniques are seen as weak, and in order to avoid "inside jobs" where employees collaborate with gamblers by performing inadequate shuffles, many casinos employ automatic shuffling machines. Your task is to simulate a shuffling machine.

The machine shuffles a deck of 54 cards according to a given random order and repeats for a given number of times. It is assumed that the initial status of a card deck is in the following order:

S1, S2, ..., S13, 
H1, H2, ..., H13, 
C1, C2, ..., C13, 
D1, D2, ..., D13, 
J1, J2

where "S" stands for "Spade", "H" for "Heart", "C" for "Club", "D" for "Diamond", and "J" for "Joker". A given order is a permutation of distinct integers in [1, 54]. If the number at the i-th position is j, it means to move the card from position i to position j. For example, suppose we only have 5 cards: S3, H5, C1, D13 and J2. Given a shuffling order {4, 2, 5, 3, 1}, the result will be: J2, H5, D13, S3, C1. If we are to repeat the shuffling again, the result will be: C1, H5, S3, J2, D13.

Input Specification:

Each input file contains one test case. For each case, the first line contains a positive integer K (≤20) which is the number of repeat times. Then the next line contains the given order. All the numbers in a line are separated by a space.

Output Specification:

For each test case, print the shuffling results in one line. All the cards are separated by a space, and there must be no extra space at the end of the line.

Sample Input:

2
36 52 37 38 3 39 40 53 54 41 11 12 13 42 43 44 2 4 23 24 25 26 27 6 7 8 48 49 50 51 9 10 14 15 16 5 17 18 19 1 20 21 22 28 29 30 31 32 33 34 35 45 46 47

Sample Output:

S7 C11 C10 C12 S1 H7 H8 H9 D8 D9 S11 S12 S13 D10 D11 D12 S3 S4 S6 S10 H1 H2 C13 D2 D3 D4 H6 H3 D13 J1 J2 C1 C2 C3 C4 D1 S5 H5 H11 H12 C6 C7 C8 C9 S2 S8 S9 H10 D5 D6 D7 H4 H13 C5

2. 题意

题目中会给出一副54张牌：初始序列为：

S1, S2, ..., S13,

H1, H2, ..., H13,

C1, C2, ..., C13,

D1, D2, ..., D13,

J1, J2

题目会给出洗牌次数K，以及洗牌次序（对应54张牌）。每次洗牌都按照洗牌次序来洗牌，洗牌规则为将第i张牌，根据次序j，调整到j的位置。

例：S1，S2，S3，S4，S5五张牌，洗牌次序为5，1，2，4，3；那么第一次洗牌完5张牌的次序为S2，S3，S5，S4，S1；再根据洗牌次序5，1，2，4，3进行洗牌；第二次洗牌完次序为S3，S5，S1，S4，S2。

题目要求根据洗牌次数K和洗牌次序，给出最终洗牌结果。

3. 思路——排序

1. 将初始洗牌次序和牌对应关系记录在pair对数组中，并单独记录下洗牌次序在数组orders中。

2. 每次洗牌根据洗牌次序先后进行排序，排序完后在通过orders数组更新pair对数组的洗牌次序。

3. 重复步骤2K次。

4. 代码

#include <iostream>
#include <algorithm>
#include <string>
#include <cstring>
#include <cstdlib>

using namespace std;

typedef pair<int, string> PII;

int cmp(PII card1, PII card2)
{
	return card1.first < card2.first;
}

int main()
{
	int n = 0;
	cin >> n;
	char chs[]{'S', 'H', 'C', 'D', 'J'};
	int orders[60];
	PII cards[60];
	int k = 1;
	// 这里主要建立序列号和牌的对应关系，并将序列号单独记录在一个数组中 
	for (int i = 0; i < 5; ++i)
	{
		if (i < 4)
		{
			for (int j = 1; j <= 13; ++j)
			{
				cin >> orders[k];
				cards[k].first = orders[k];
				cards[k++].second = chs[i] + to_string(j);
			}
		} else
		{
			cin >> orders[k];
			cards[k].first = orders[k];
			cards[k++].second = "J1";
			cin >> orders[k];
			cards[k].first = orders[k];
			cards[k++].second = "J2";
		}
	}
	// 每进行一次排序，都要将序列号重新更新为输入时的序列号重新排序
	// 根据题目要求，进行n次重排，相当于进行了n次洗牌 
	while (n--)
	{
		sort(cards + 1, cards + 55, cmp);
		for (int i = 1; i < 55; ++i)
			cards[i].first = orders[i];
	}
	for (int i = 1; i < 55; ++i)
	{
		if (i != 1) cout << " " << cards[i].second;
		else cout << cards[i].second;
	}
	return 0;
}