Queue Reconstruction by Height

Jin Shang bio photo By Jin Shang

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]]

Solution:

Sort the group of highest people, their second is their order in the list now.

Sort the second highest, their second is there order in the list. …

class Solution {
public:
    vector<vector<int>> reconstructQueue(vector<vector<int>>& people) {
        sort(people.begin(), people.end(), [](vector<int>& a, vector<int>& b){
            return (a[0] > b[0]) || (a[0] == b[0] && a[1] < b[1]);
        });
        vector<vector<int>> ans;
        for(auto &p: people){
            ans.insert(ans.begin()+p[1],p);
        }
        return ans;
    }
};