Maximum Product Subarray

Problem

Return the largest product of a non-empty contiguous subarray of nums.

Track both the maximum and minimum product ending at the current position, since multiplying a negative minimum by a negative value can create the new maximum. Return 0 for an empty list.

Hint

Keep the running minimum too: a very negative product can flip into the best answer.

Test cases

case 1

in: [[2,3,-2,4]]

expected: 6

case 2

in: [[-2,0,-1]]

expected: 0

case 3

in: [[-2,3,-4]]

expected: 24

case 4

in: [[-2]]

expected: -2

case 5

in: [[0,2]]

expected: 2

case 6

in: [[]]

expected: 0

Starter codePython

def max_product(nums):
    # Your code here
    pass

6 test cases · run your code against them in the editor