[LC] 3066 Minimum Operations to Exceed Threshold Value II

Java

import java.util.PriorityQueue;
import java.util.Queue;

/**
 * <a href="https://leetcode.cn/problems/minimum-operations-to-exceed-threshold-ii/">Minimum Operations To Exceed Threshold II</a>
 * 数组；模拟；堆（优先队列）
 */
class Solution {
    public int minOperations(int[] nums, int k) {
        Queue<Long> queue = new PriorityQueue<>();
        for (long num : nums) {
            queue.add(num);
        }

        int cnt = 0;
        while (queue.size() > 1 && queue.peek() < k) {
            long min1 = queue.remove();
            long min2 = queue.remove();
            queue.add(min1 * 2 + min2);
            cnt++;
        }
        return cnt;
    }
}

Go

import "container/heap"

func minOperations(nums []int, k int) int {
    res := 0
    pq := &MinHeap{}
    heap.Init(pq)
    for _, num := range nums {
        heap.Push(pq, num)
    }

    for (*pq)[0] < k {
        x := heap.Pop(pq).(int)
        y := heap.Pop(pq).(int)
        heap.Push(pq, x+x+y)
        res++
    }

    return res
}

type MinHeap []int

func (h *MinHeap) Len() int {
    return len(*h)
}

func (h *MinHeap) Less(i, j int) bool {
    return (*h)[i] < (*h)[j]
}

func (h *MinHeap) Swap(i, j int) {
    (*h)[i], (*h)[j] = (*h)[j], (*h)[i]
}

func (h *MinHeap) Push(x interface{}) {
    *h = append(*h, x.(int))
}

func (h *MinHeap) Pop() interface{} {
    old := *h
    n := len(old)
    x := old[n-1]
    *h = old[0 : n-1]
    return x
}