LeetCode | 152. Maximum Product Subarray

 

題目：

Given an integer array nums, find the contiguous subarray within an array (containing at least one number) which has the largest product.

Example 1:

Input: [2,3,-2,4]
Output: 6
Explanation: [2,3] has the largest product 6.

Example 2:

Input: [-2,0,-1]
Output: 0
Explanation: The result cannot be 2, because [-2,-1] is not a subarray.

 

程式碼：

class Solution {
public:
    int maxProduct(vector<int>& nums) {
        if (nums.size() < 1)
			return 0;
		int maxValue, maxP, minP;
		maxValue = maxP = minP = nums[0];
		for (int i = 1; i < nums.size(); i++)
		{
			if (nums[i] < 0)
				swap(maxP, minP);
			maxP = max(nums[i], nums[i] * maxP);
			minP = min(nums[i], nums[i] * minP);
			maxValue = max(maxValue, maxP);
		}
		return maxValue;
    }
};