Queue Reconstruction by Height问题及解法

问题描述：

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.

示例：

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]]

问题分析（这里省事了，直接摘抄英文~）：

1.Pick out tallest group of people and sort them in a subarray (S). Since there's no other groups of people taller than them, therefore each guy's index will be just as same as his k value.

2.For 2nd tallest group (and the rest), insert each one of them into (S) by k value. So on and so forth.

过程详见代码：

class Solution {public:    vector<pair<int, int>> reconstructQueue(vector<pair<int, int>>& people) {        auto com = [](const pair<int, int>& p1, const pair<int, int>& p2){return p1.first > p2.first || (p1.first == p2.first && p1.second < p2.second);};sort(people.begin(), people.end(), com);vector<pair<int, int>> res;for (auto p : people){res.insert(res.begin() + p.second, p);}return res;    }};