Create 0665-non-decreasing-array.scala

Author: akbar-yusupov

scala/0665-non-decreasing-array.scala

@@ -0,0 +1,16 @@
+object Solution {
+    def checkPossibility(nums: Array[Int]): Boolean = {
+        @scala.annotation.tailrec
+        def helper(i: Int = 1, mismatch: Int = 0, last: Int = nums.head): Boolean =
+            if (i == nums.length) true
+            else if (nums(i) >= last) helper(i + 1, mismatch, nums(i))
+            else if (mismatch > 0) false
+            else if (i == nums.length - 1) true
+            else if (nums(i - 1) <= nums(i + 1)) helper(i + 1, mismatch + 1, nums(i))
+            else if (i == 1 && nums(i) <= nums(i + 1)) helper(i + 1, mismatch + 1, nums(i))
+            else if (i > 1 && nums(i - 2) <= nums(i)) helper(i + 1, mismatch + 1, nums(i))
+            else false
+
+        helper()
+  }
+}