leetcode 941

leetcode/941/941.py

@@ -0,0 +1,24 @@
+class Solution:
+    def validMountainArray(self, A: List[int]) -> bool:
+        if len(A) < 3:
+            return False
+        up = True
+        lst = A[1]
+        if A[0] >= A[1]:
+            return False
+        for a in A[2:]:
+            if up:
+                if a > lst:
+                    lst = a
+                elif a == lst:
+                    return False
+                else:
+                    # a < lst
+                    lst = a
+                    up = False
+            else:
+                if a >= lst:
+                    return False
+                else:
+                    lst = a
+        return up == False

leetcode/941/problem.json

@@ -0,0 +1,28 @@
+{
+    "name": "validMountainArray",
+    "samples": [
+        {
+            "in": [
+                2,
+                1
+            ],
+            "out": false
+        },
+        {
+            "in": [
+                2,
+                1
+            ],
+            "out": false
+        },
+        {
+            "in": [
+                0,
+                3,
+                2,
+                1
+            ],
+            "out": true
+        }
+    ]
+}