Maximum Product Subarray

Author: gavinfish

152 Maximum Product Subarray.py

@@ -0,0 +1,24 @@
+'''
+Find the contiguous subarray within an array (containing at least one number) which has the largest product.
+
+For example, given the array [2,3,-2,4],
+the contiguous subarray [2,3] has the largest product = 6.
+'''
+
+class Solution(object):
+    def maxProduct(self, nums):
+        """
+        :type nums: List[int]
+        :rtype: int
+        """
+        positive, negative = nums[0], nums[0]
+        result = nums[0]
+        for num in nums[1:]:
+            positive, negative = max(num, positive * num, negative * num), min(num,
+                                                                               positive * num, negative * num)
+            result = max(result, positive)
+        return result
+
+
+if __name__ == "__main__":
+    assert Solution().maxProduct([2, 3, -2, 4]) == 6