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:
2 <= skill.length <= 105
skill.length
is even.1 <= skill[i] <= 1000
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;
}
}