SlidingWindowMax.java

import java.util.*;

public class SlidingWindowMaximum {
    public static int[] maxSlidingWindow(int[] nums, int k) {
        int n = nums.length;
        int[] result = new int[n - k + 1];
        PriorityQueue<int[]> maxHeap = new PriorityQueue<>((a, b) -> b[0] - a[0]); // Max heap based on value

        for (int i = 0; i < n; i++) {
            //add current
            maxHeap.offer(new int[]{nums[i], i});

            // remove elements outside the current window
            while (maxHeap.peek()[1] <= i - k) {
                maxHeap.poll();
            }

            // Store the max for the current window
            if (i >= k - 1) {
                result[i - k + 1] = maxHeap.peek()[0];
            }
        }

        return result;
    }

    public static void main(String[] args) {
        int[] nums = {1, 3, -1, -3, 5, 3, 6, 7};
        int k = 3;
        System.out.println(Arrays.toString(maxSlidingWindow(nums, k)));
    }
}