LeetCode-in-Java

2491. Divide Players Into Teams of Equal Skill

Medium

You are given a positive integer array skill of even length n where skill[i] denotes the skill of the ith player. Divide the players into n / 2 teams of size 2 such that the total skill of each team is equal.

The chemistry of a team is equal to the product of the skills of the players on that team.

Return the sum of the chemistry of all the teams, or return -1 if there is no way to divide the players into teams such that the total skill of each team is equal.

Example 1:

Input: skill = [3,2,5,1,3,4]

Output: 22

Explanation: Divide the players into the following teams: (1, 5), (2, 4), (3, 3), where each team has a total skill of 6. The sum of the chemistry of all the teams is: 1 * 5 + 2 * 4 + 3 * 3 = 5 + 8 + 9 = 22.

Example 2:

Input: skill = [3,4]

Output: 12

Explanation: The two players form a team with a total skill of 7. The chemistry of the team is 3 * 4 = 12.

Example 3:

Input: skill = [1,1,2,3]

Output: -1

Explanation: There is no way to divide the players into teams such that the total skill of each team is equal.

Constraints:

Solution

import java.util.Arrays;

public class Solution {
    public long dividePlayers(int[] skill) {
        int i = 0;
        int j = skill.length - 1;
        Arrays.sort(skill);
        int sum = skill[i] + skill[j];
        long p = 0;
        while (i < j) {
            if (skill[i] + skill[j] != sum) {
                return -1;
            }
            p += ((long) skill[i] * skill[j]);
            i++;
            j--;
        }
        return p;
    }
}