Update 1438-longest-continuous-subarray-with-absolute-diff-less-than-or-equal-to-limit.js

Author: everthis

1438-longest-continuous-subarray-with-absolute-diff-less-than-or-equal-to-limit.js

@@ -23,3 +23,78 @@ const longestSubarray = function(nums, limit) {
     }
     return j - i; 
 };
+
+// another
+
+/**
+ * @param {number[]} nums
+ * @param {number} limit
+ * @return {number}
+ */
+const longestSubarray = function (nums, limit) {
+  const maxDq = new Deque(), minDq = new Deque(), n = nums.length
+  let l = 0, r = 0
+  let res = 0
+  for(r = 0; r < n; r++) {
+    const cur = nums[r]
+    while(!maxDq.isEmpty() && maxDq.last() < cur) {
+      maxDq.pop()
+    }
+    maxDq.enqueue(cur)
+    while(!minDq.isEmpty() && minDq.last() > cur) {
+      minDq.pop()
+    }
+    minDq.enqueue(cur)
+
+    while(maxDq.first() - minDq.first() > limit) {
+      if(nums[l] === maxDq.first()) maxDq.dequeue()
+      if(nums[l] === minDq.first()) minDq.dequeue()
+      l++
+    }
+    res = Math.max(res, r - l + 1)
+  }
+  return res
+}
+
+class Deque {
+  constructor() {
+    this.head = new Node()
+    this.tail = this.head
+  }
+
+  isEmpty() {
+    return this.head.next === null
+  }
+
+  first() {
+    return this.head.next.value
+  }
+
+  last() {
+    return this.tail.value
+  }
+
+  dequeue() {
+    this.head = this.head.next
+    this.head.prev = null
+  }
+
+  enqueue(value) {
+    this.tail.next = new Node(value)
+    this.tail.next.prev = this.tail
+    this.tail = this.tail.next
+  }
+
+  pop() {
+    this.tail = this.tail.prev
+    this.tail.next = null
+  }
+}
+
+class Node {
+  constructor(value) {
+    this.value = value
+    this.next = null
+    this.prev = null
+  }
+}