Create validate-stack-sequences.py

Author: kamyu104

Python/validate-stack-sequences.py

@@ -0,0 +1,18 @@
+# Time:  O(n)
+# Space: O(n)
+
+class Solution(object):
+    def validateStackSequences(self, pushed, popped):
+        """
+        :type pushed: List[int]
+        :type popped: List[int]
+        :rtype: bool
+        """
+        i = 0
+        s = []
+        for v in pushed:
+            s.append(v)
+            while s and i < len(popped) and s[-1] == popped[i]:
+                s.pop()
+                i += 1
+        return i == len(popped)