From cbaaa6398ae5a3275728efd446c5a03701bff7bd Mon Sep 17 00:00:00 2001
From: nanhuaibeian <49868746+nanhuaibeian@users.noreply.github.com>
Date: Thu, 13 May 2021 09:43:25 +0800
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---
 problems/0239.滑动窗口最大值.md | 53 ++++++++++++++++++++++++++
 1 file changed, 53 insertions(+)

diff --git a/problems/0239.滑动窗口最大值.md b/problems/0239.滑动窗口最大值.md
index 709fa09e..781bfa6f 100644
--- a/problems/0239.滑动窗口最大值.md
+++ b/problems/0239.滑动窗口最大值.md
@@ -207,7 +207,60 @@ public:
 
 
 Java：
+```Java
+//自定义数组
+class MyQueue {
+    Deque<Integer> deque = new LinkedList<>();
+    //弹出元素时，比较当前要弹出的数值是否等于队列出口的数值，如果相等则弹出
+    //同时判断队列当前是否为空
+    void poll(int val) {
+        if (!deque.isEmpty() && val == deque.peek()) {
+            deque.poll();
+        }
+    }
+    //添加元素时，如果要添加的元素大于入口处的元素，就将入口元素弹出
+    //保证队列元素单调递减
+    //比如此时队列元素3,1，2将要入队，比1大，所以1弹出，此时队列：3,2
+    void add(int val) {
+        while (!deque.isEmpty() && val > deque.getLast()) {
+            deque.removeLast();
+        }
+        deque.add(val);
+    }
+    //队列队顶元素始终为最大值
+    int peek() {
+        return deque.peek();
+    }
+}
 
+class Solution {
+    public int[] maxSlidingWindow(int[] nums, int k) {
+        if (nums.length == 1) {
+            return nums;
+        }
+        int len = nums.length - k + 1;
+        //存放结果元素的数组
+        int[] res = new int[len];
+        int num = 0;
+        //自定义队列
+        MyQueue myQueue = new MyQueue();
+        //先将前k的元素放入队列
+        for (int i = 0; i < k; i++) {
+            myQueue.add(nums[i]);
+        }
+        res[num++] = myQueue.peek();
+        for (int i = k; i < nums.length; i++) {
+            //滑动窗口移除最前面的元素，移除是判断该元素是否放入队列
+            myQueue.poll(nums[i - k]);
+            //滑动窗口加入最后面的元素
+            myQueue.add(nums[i]);
+            //记录对应的最大值
+            res[num++] = myQueue.peek();
+        }
+        return res;
+    }
+}
+```
 
 Python：