2020-02-12

Author: JiayangWu

0946.验证栈序列/0946-验证栈序列.py

@@ -5,51 +5,12 @@ def validateStackSequences(self, pushed, popped):
         :type popped: List[int]
         :rtype: bool
         """
-        
-        stack = []
-        i = 0
-        for item in pushed:
-            stack.append(item)
-            while(stack and popped[i] == stack[-1]):
-                stack.pop()
-                i += 1
-        return stack == []
-        
-        
-        
-        
-        
-        
-        
-        
-        
-        
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-        
-        
-        
-        
-        
-        
-        
-        
-        
-        
-        
-        l = len(pushed)
-        
-        stack = list()
-
-        
-        for i in range(0, l):
-            stack.append(pushed[i])
-            while(stack and stack[-1] == popped[0]):
-                stack = stack[:-1]
-                popped = popped[1:]
-
-        return stack == []
-
-                
-                
-        
+        s = []
+        popped = popped[::-1]
+        for num in pushed:
+            s.append(num)
+            while s and popped and s[-1] == popped[-1]:
+                s.pop()
+                popped.pop()
+        
+        return not s and not popped