[数据结构与算法]LeetCode1996. 游戏中弱角色的数量

相关信息：

LeetCode链接:
https://leetcode-cn.com/problems/the-number-of-weak-characters-in-the-game/

代码：

//作者:LeetCodeSolution
import java.util.Arrays;

public class L1996 {
    public static void main(String[] args) {
        //Test
        int[][] properties = { {4, 3},{10, 4}, {1, 2}};
        Solution1996 solution1996 = new Solution1996();

        int ans = solution1996.numberOfWeakCharacters(properties);
        System.out.println(ans);
    }
}

class Solution1996 {
    public int numberOfWeakCharacters(int[][] properties) {
        /*reorder the properties in descending order
        * { {4, 3},{10, 4}, {1, 2}} -> {{10, 4}, {4, 3}, {1, 2}};
        * the implementation of comparators
        * (o1, o2) ->   o1[0] == o2[0] ? (o1[1] - o2[1]) : (o2[0] - o1[0])
        * */
        Arrays.sort(properties, (o1, o2) ->
                //returns a negative value when o2 < o1, and a positive value when o2 > o1
                o1[0] == o2[0] ? (o1[1] - o2[1]) : (o2[0] - o1[0])
        );

        int maxDef = 0;
        int ans = 0;
        for (int[] p : properties) {
            if (maxDef > p[1]) {
                ans++;
            } else {
                maxDef = p[1];
            }
        }
        return ans;
    }
}