Merge pull request soapyigu#362 from soapyigu/SlidingWindow

Build a sliding window solutions set and add a solution to the Longes…

SlidingWindow/LongestContinuousSubarrayLimit.swift

@@ -0,0 +1,41 @@
+/**
+ * Question Link: https://leetcode.com/problems/longest-continuous-subarray-with-absolute-diff-less-than-or-equal-to-limit/description/
+ * Primary idea: Slding window, use max and min queues to track largest difference along the way. Move left pointer to get the potential result.
+ *
+ * Note: k may be invalid, mention that with interviewer
+ * Time Complexity: O(n), Space Complexity: O(n)
+ *
+ */
+
+class LongestContinuousSubarrayLimit {
+    func longestSubarray(_ nums: [Int], _ limit: Int) -> Int {
+        var maxQueue = [Int](), minQueue = [Int](), left = 0, size = 0
+
+        for (i, num) in nums.enumerated() {
+            while !maxQueue.isEmpty && maxQueue.last! < num {
+                maxQueue.removeLast()
+            }
+            while !minQueue.isEmpty && minQueue.last! > num {
+                minQueue.removeLast()
+            }
+
+            maxQueue.append(num)
+            minQueue.append(num)
+
+            if maxQueue.first! - minQueue.first! > limit {
+                if nums[left] == maxQueue.first! {
+                    maxQueue.removeFirst()
+                }
+                if nums[left] == minQueue.first! {
+                    minQueue.removeFirst()
+                }
+
+                left += 1
+            }
+
+            size = max(size, i - left + 1)
+        }
+
+        return size
+    }
+}