Merge pull request #110 from skanarul8002/main

DSA in Java: find maximum element in every sliding window of size k

Author: Ritikraja07

SlidingWindowMaximum.java

@@ -0,0 +1,39 @@
+import java.util.ArrayList;
+import java.util.Deque;
+import java.util.LinkedList;
+import java.util.List;
+
+public class SlidingWindowMaximum {
+
+  // Function to find maximum element in every sliding window of size k
+  public static List<Integer> maxSlidingWindow(int[] nums, int k) {
+    List<Integer> result = new ArrayList<>();
+    if (nums == null || nums.length == 0) {
+      return result;
+    }
+
+    Deque<Integer> deque = new LinkedList<>();
+
+    for (int i = 0; i < nums.length; i++) {
+      if (!deque.isEmpty() && deque.peekFirst() < i - k + 1) {
+        deque.pollFirst();
+      }
+      while (!deque.isEmpty() && nums[deque.peekLast()] < nums[i]) {
+        deque.pollLast();
+      }
+      deque.offerLast(i);
+      if (i >= k - 1) {
+        result.add(nums[deque.peekFirst()]);
+      }
+    }
+    return result;
+  }
+
+  public static void main(String[] args) {
+    int[] nums = { 1, 3, -1, -3, 5, 3, 6, 7 };
+    int k = 3;
+
+    List<Integer> result = maxSlidingWindow(nums, k);
+    System.out.println("Maximum elements in each sliding window of size " + k + ": " + result);
+  }
+}