406. Queue Reconstruction by Height.md

406. Queue Reconstruction by Height

https://leetcode.com/problems/queue-reconstruction-by-height/

题目

Suppose you have a random list of people standing in a queue. Each person is described by a pair of integers (h, k), where h is the height of the person and k is the number of people in front of this person who have a height greater than or equal to h. Write an algorithm to reconstruct the queue.

Note: The number of people is less than 1,100.

Example

Input:
[[7,0], [4,4], [7,1], [5,0], [6,1], [5,2]]

Output:
[[5,0], [7,0], [5,2], [6,1], [4,4], [7,1]]

代码

• people =【身高，index】，身高按高到低排序，index 从小到大排序。
• people 排好序后，一个个按照自己的 index 插到 result 中即可。

class Solution:
    def reconstructQueue(self, people: List[List[int]]) -> List[List[int]]:
        
        # greedy + insert
        people.sort(key = lambda x: (-x[0], x[1]))
        res = []
        
        for p in people:
            res.insert(p[1], p)
        return res