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7-reverse-integer/7-reverse-integer.py

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+class Solution(object):
+    def reverse(self, x):
+        """
+        :type x: int
+        :rtype: int
+        """
+        MAX_32_VALUE = 2147483648
+        REVERSED_MAX_32_VALUE = 463847412
+        
+        # Check negative 
+        isNegative = False
+        if x < 0:
+            x = -x
+            isNegative = True
+            
+        # Check if reversed is outside of [-2**31, 2**31 - 1]
+        if x > 10**9:
+            for i in range(1, 10):
+                xMod10i = x % (10**i)
+                reversedMax = REVERSED_MAX_32_VALUE % (10**i)
+                print("i:" + str(i) + "->" + str(xMod10i) + " " + str(reversedMax))
+                if xMod10i > reversedMax:
+                    return 0
+                elif xMod10i < reversedMax:
+                    break
+            
+        
+        # Reverse integer
+        reversedInt = 0
+        while x > 0:
+            reversedInt *= 10
+            reversedInt += x % 10
+            x = int(x / 10)
+            
+        return -reversedInt if isNegative else reversedInt