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# 題目敘述

Given an integer array nums and an integer k , return the kth largest element in the array.

Note that it is the kth largest element in the sorted order, not the kth distinct element.

Can you solve it without sorting?

# Example 1

Input: nums = [3,2,1,5,6,4], k = 2
Output: 5

# Example 2

Input: nums = [3,2,3,1,2,4,5,5,6], k = 4
Output: 4

# 解題思路

Use the PriorityQueue which is a data structure.

# Solution

import java.util.Comparator;
import java.util.PriorityQueue;
class Solution {
    public int findKthLargest(int[] nums, int k) {
        PriorityQueue<Integer> PQ = new PriorityQueue<>(new PQComparator());
        for (int num : nums) {
            PQ.add(num);
        }
        int ans = 0;
        for (int i = 0; i < k; i++) {
            ans = PQ.poll();
        }
        return ans;
    }
}
class PQComparator implements Comparator<Integer> {
    @Override
    public int compare(Integer number1, Integer number2) {
        int value = number1.compareTo(number2);
        // elements are sorted in reverse order
        if (value > 0) {
            return -1;
        } else if (value < 0) {
            return 1;
        } else {
            return 0;
        }
    }
}




單字
distinct
清楚的 adj.
  • There's a distinct smell of cigarettes in here.
clearly noticeable; that certainly exists
片語 & 搭配詞
smell of + sth
... 的香味