950.Reveal Cards In Increasing Order(按递增顺序显示卡牌)

Description

In a deck of cards, every card has a unique integer. You can order the deck in any order you want.

Initially, all the cards start face down (unrevealed) in one deck.

Now, you do the following steps repeatedly, until all cards are revealed:

Take the top card of the deck, reveal it, and take it out of the deck.
If there are still cards in the deck, put the next top card of the deck at the bottom of the deck.
If there are still unrevealed cards, go back to step 1. Otherwise, stop.

Return an ordering of the deck that would reveal the cards in increasing order.

The first entry in the answer is considered to be the top of the deck.

牌组中的每张卡牌都对应有一个唯一的整数。你可以按你想要的顺序对这套卡片进行排序。

最初，这些卡牌在牌组里是正面朝下的（即，未显示状态）。

现在，重复执行以下步骤，直到显示所有卡牌为止：

从牌组顶部抽一张牌，显示它，然后将其从牌组中移出。
如果牌组中仍有牌，则将下一张处于牌组顶部的牌放在牌组的底部。
如果仍有未显示的牌，那么返回步骤 1。否则，停止行动。

返回能以递增顺序显示卡牌的牌组顺序。

答案中的第一张牌被认为处于牌堆顶部。

题目链接：https://leetcode.com/problems/reveal-cards-in-increasing-order/

Difficulty: medium

Example 1:

Input: [17,13,11,2,3,5,7]
Output: [2,13,3,11,5,17,7]
Explanation: 
We get the deck in the order [17,13,11,2,3,5,7] (this order doesn't matter), and reorder it.
After reordering, the deck starts as [2,13,3,11,5,17,7], where 2 is the top of the deck.
We reveal 2, and move 13 to the bottom.  The deck is now [3,11,5,17,7,13].
We reveal 3, and move 11 to the bottom.  The deck is now [5,17,7,13,11].
We reveal 5, and move 17 to the bottom.  The deck is now [7,13,11,17].
We reveal 7, and move 13 to the bottom.  The deck is now [11,17,13].
We reveal 11, and move 17 to the bottom.  The deck is now [13,17].
We reveal 13, and move 17 to the bottom.  The deck is now [17].
We reveal 17.
Since all the cards revealed are in increasing order, the answer is correct.

Note:

1 <= A.length <= 1000
1 <= A[i] <= 10^6
A[i] != A[j] for all i != j

分析

由题意知，是每显示一张卡片，将下一张（如果有）放到最后面；
相当于在一排位置上，循环填坑，每次跳两个位置，被占用的坑忽略；
首先将数组排序，按顺序填入坑中；形如[-,-,-,-,-,-,-]中填入[2,3,5,7,11,13,17];
接下来每次填入一个数字的结果如下：[2,-,-,-,-,-,-]->[2,-,3,-,-,-,-]->[2,-,3,-,5,-,-]->[2,-,3,-,5,-,7]->[2,-,3,11,5,-,7]->[2,13,3,11,5,-,7]->[2,13,3,11,5,17,7];
如上即是返回结果。

参考代码

class Solution:
def deckRevealedIncreasing(self, deck):
    deck.sort()
    A=[0]*len(deck)
    index=0
    judge=[i for i in range(len(deck))]
    for i in range(len(A)):
        A[judge[index]]=deck[i]
        judge=judge[:index]+judge[index+1:]
        index+=1
        if(len(judge)):
            index%=len(judge)
    return A