Marc Lester Tan

Is there any other way to solve this without using PriorityQueue? One could use a list and sort it always everytime a new non-zero value is created from smashing the rocks together but that won’t be that much different than using PriorityQueue which sorts the elements in every offer

import java.util.*
import kotlin.Comparator

class Solution {
    fun lastStoneWeight(stones: IntArray): Int {
        var map = PriorityQueue(stones.size, Comparator<Int> { a, b -> 
            when {
                a < b -> 1
                a == b -> 0
                else -> -1
            }        
        })
        
        stones.forEach { map.offer(it) }        
        
        while(!map.isEmpty()) {
            if(map.size == 1) break
            val y = map.poll()
            val x = map.poll()
            
            val diff = when {
                x == y -> 0
                else -> y - x
            }
            
            map.offer(diff)
        }
        
        return map.first()
    }
}

Runtime: 136 ms, faster than 96.88% of Kotlin online submissions for Last Stone Weight.
Memory Usage: 32.3 MB, less than 100.00% of Kotlin online submissions for Last Stone Weight.