[LeetCode] Queue Reconstruction by Height

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]]

给定一个队列，要求按照要求给队列排序。

pair的第一个元素代表身高，第二个元素代表小于等于该身高的人数的个数。

lambda表达式的简洁性

按照pair的要求来排序这个队列

1、将给定队列按照以下规则排序：按照first的从大到小排序，同等高度时按照second从小到大排序。

2、然后遍历这个队列，也就是从大到小选择。res.begin() + p.second表示在当前元素此时队列中插入的位置。

class Solution {
public:
    vector<pair<int, int>> reconstructQueue(vector<pair<int, int>>& people) {
        sort(people.begin(), people.end(), [](const pair<int, int>& a, const pair<int, int>& b) { return (a.first > b.first) || (a.first == b.first && a.second < b.second);});
        vector<pair<int, int>> res;
        for (auto& p : people) {
            res.insert(res.begin() + p.second, p);
        }
        return res;
    }
};
// 36 ms