isValid - AC

Author: jcp0578

leecode/有效的括号/isValid.py

@@ -1,7 +1,7 @@
 #!/usr/bin/python3
 # -*- coding: utf-8 -*-
 '''
-AC but not a good solution
+AC
 '''
 import time
 
@@ -12,23 +12,18 @@ def isValid(self, s):
         :type s: str
         :rtype: bool
         """
-        trantab = s.maketrans("()[]{}", "142536")
-        s = s.translate(trantab)
-        s = list(map(int, s))
-        stack = []
+        left = {'[': 1, '(':2, '{':3}
+        right = {']':1, ')':2, '}':3}
+        left_s = []
         for i in s:
-            if i < 4:
-                stack.append(i)
+            if i in left:
+                left_s.append(left[i])
             else:
-                try:
-                    if i - stack.pop() == 3:
-                        pass
-                    else:
-                        return False
-                except IndexError:
+                if len(left_s) == 0:
+                    return False
+                if left_s.pop() != right[i]:
                     return False
-        else:
-            return len(stack)==0
+        return len(left_s) == 0
 
 
 if __name__ == "__main__":
@@ -60,4 +55,6 @@ def isValid(self, s):
                     return False
                 stack.pop()
         return len(stack) == 0
+
+
 '''