1753. Maximum Score From Removing Stones

package LeetCode_1753

/**
 * 1753. Maximum Score From Removing Stones
 * https://leetcode.com/problems/maximum-score-from-removing-stones/
 * You are playing a solitaire game with three piles of stones of sizes a??????, b,?????? and c?????? respectively.
 * Each turn you choose two different non-empty piles, take one stone from each, and add 1 point to your score.
 * The game stops when there are fewer than two non-empty piles (meaning there are no more available moves).
Given three integers a?????, b,????? and c?????, return the maximum score you can get.

Example 1:
Input: a = 2, b = 4, c = 6
Output: 6
Explanation: The starting state is (2, 4, 6). One optimal set of moves is:
- Take from 1st and 3rd piles, state is now (1, 4, 5)
- Take from 1st and 3rd piles, state is now (0, 4, 4)
- Take from 2nd and 3rd piles, state is now (0, 3, 3)
- Take from 2nd and 3rd piles, state is now (0, 2, 2)
- Take from 2nd and 3rd piles, state is now (0, 1, 1)
- Take from 2nd and 3rd piles, state is now (0, 0, 0)
There are fewer than two non-empty piles, so the game ends. Total: 6 points.

Example 2:
Input: a = 4, b = 4, c = 6
Output: 7
Explanation: The starting state is (4, 4, 6). One optimal set of moves is:
- Take from 1st and 2nd piles, state is now (3, 3, 6)
- Take from 1st and 3rd piles, state is now (2, 3, 5)
- Take from 1st and 3rd piles, state is now (1, 3, 4)
- Take from 1st and 3rd piles, state is now (0, 3, 3)
- Take from 2nd and 3rd piles, state is now (0, 2, 2)
- Take from 2nd and 3rd piles, state is now (0, 1, 1)
- Take from 2nd and 3rd piles, state is now (0, 0, 0)
There are fewer than two non-empty piles, so the game ends. Total: 7 points.

Example 3:
Input: a = 1, b = 8, c = 8
Output: 8
Explanation: One optimal set of moves is to take from the 2nd and 3rd piles for 8 turns until they are empty.
After that, there are fewer than two non-empty piles, so the game ends.

Constraints:
1 <= a, b, c <= 10^5
 * */
class Solution {
    /*
    * solution: greedy to keep decreasing 2 biggest number until 0,
    * Time:O(max(a,b,c)), Space:O(1)
    * */
    fun maximumScore(a: Int, b: Int, c: Int): Int {
        val nums = intArrayOf(a, b, c)
        nums.sort()
        var result = 0
        while ((nums[0] > 0 && nums[1] > 0) || (nums[0] > 0 && nums[2] > 0) || (nums[1] > 0 && nums[2] > 0)) {
            result++
            nums[1]--
            nums[2]--
            nums.sort()
        }
        return result
    }
}