queue-reconstruction-by-height

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

// https://discuss.leetcode.com/topic/60394/easy-concept-with-python-c-java-solution/5
// 先按照高度从大到小排,同样高度按人数从小到大排
// 然后按照前面的人数,来进行插入

import java.util.Arrays;
import java.util.Comparator;
import java.util.LinkedList;
import java.util.List;

public class Solution {
    public int[][] reconstructQueue(int[][] people) {

        Arrays.sort(people, new Comparator<int[]>() {
            @Override
            public int compare(int[] o1, int[] o2) {
                return o1[0] == o2[0] ? o1[1] - o2[1] : o2[0] - o1[0];
            }
        });

        List<int[]> res = new LinkedList<>();
        for (int[] cur : people) {
            res.add(cur[1], cur);
        }

        return res.toArray(new int[people.length][]);
    }
    
    /*
    public static void main(String[] args) {
        // write your code here
        System.out.println("Hello");
        int[][] people = {{7,0}, {4,4}, {7,1}, {5,0}, {6,1}, {5,2}};


        Main mn = new Main();
        int[][] ret = mn.reconstructQueue(people);
        StringBuilder sb = new StringBuilder();
        for (int i=0; i<ret.length; i++) {
            for (int j=0; j<ret[0].length; j++) {
                sb.append(ret[i][j]);
                sb.append(',');
            }
            sb.append('|');
        }
        System.out.println(sb.toString());

    }
    */
}

注意这一句

return res.toArray(new int[people.length][]);

经过实验，填写 (new int[][2]) 或者 (new int[][]) 都是不行的。需要在前一个下标处填写。而填写的数值范围是0到length，再大再小都不行。在这个范围内，返回的结果都是一样的。