# 1996. The Number of Weak Characters in the Game

## Description

You are playing a game that contains multiple characters, and each of the characters has two main properties: attack and defense. You are given a 2D integer array properties where properties[i] = [attacki, defensei] represents the properties of the ith character in the game.

A character is said to be weak if any other character has both attack and defense levels strictly greater than this character's attack and defense levels. More formally, a character i is said to be weak if there exists another character j where attackj > attacki and defensej > defensei.

Return the number of weak characters.

Example 1:

Input: properties = [[5,5],[6,3],[3,6]]
Output: 0
Explanation: No character has strictly greater attack and defense than the other.


Example 2:

Input: properties = [[2,2],[3,3]]
Output: 1
Explanation: The first character is weak because the second character has a strictly greater attack and defense.


Example 3:

Input: properties = [[1,5],[10,4],[4,3]]
Output: 1
Explanation: The third character is weak because the second character has a strictly greater attack and defense.


Constraints:

• 2 <= properties.length <= 105
• properties[i].length == 2
• 1 <= attacki, defensei <= 105

## Solutions

• class Solution {
public int numberOfWeakCharacters(int[][] properties) {
Arrays.sort(properties, (a, b) -> b[0] - a[0] == 0 ? a[1] - b[1] : b[0] - a[0]);
int ans = 0, mx = 0;
for (var x : properties) {
if (x[1] < mx) {
++ans;
}
mx = Math.max(mx, x[1]);
}
return ans;
}
}

• class Solution {
public:
int numberOfWeakCharacters(vector<vector<int>>& properties) {
sort(properties.begin(), properties.end(), [&](auto& a, auto& b) { return a[0] == b[0] ? a[1] < b[1] : a[0] > b[0]; });
int ans = 0, mx = 0;
for (auto& x : properties) {
ans += x[1] < mx;
mx = max(mx, x[1]);
}
return ans;
}
};

• class Solution:
def numberOfWeakCharacters(self, properties: List[List[int]]) -> int:
properties.sort(key=lambda x: (-x[0], x[1]))
ans = mx = 0
for _, x in properties:
ans += x < mx
mx = max(mx, x)
return ans


• func numberOfWeakCharacters(properties [][]int) (ans int) {
sort.Slice(properties, func(i, j int) bool {
a, b := properties[i], properties[j]
if a[0] == b[0] {
return a[1] < b[1]
}
return a[0] > b[0]
})
mx := 0
for _, x := range properties {
if x[1] < mx {
ans++
} else {
mx = x[1]
}
}
return
}

• function numberOfWeakCharacters(properties: number[][]): number {
properties.sort((a, b) => (a[0] == b[0] ? a[1] - b[1] : b[0] - a[0]));
let ans = 0;
let mx = 0;
for (const [, x] of properties) {
if (x < mx) {
ans++;
} else {
mx = x;
}
}
return ans;
}


• /**
* @param {number[][]} properties
* @return {number}
*/
var numberOfWeakCharacters = function (properties) {
properties.sort((a, b) => (a[0] == b[0] ? a[1] - b[1] : b[0] - a[0]));
let ans = 0;
let mx = 0;
for (const [, x] of properties) {
if (x < mx) {
ans++;
} else {
mx = x;
}
}
return ans;
};