Given an integer array nums, find a contiguous non-empty subarray within the array that has the largest product, and return the product.
It is guaranteed that the answer will fit in a 32-bit integer.
A subarray is a contiguous subsequence of the array.
Example 1:
Input: nums = [2,3,-2,4]
Output: 6
Explanation: [2,3] has the largest product 6.
Example 2:
Input: nums = [-2,0,-1]
Output: 0
Explanation: The result cannot be 2, because [-2,-1] is not a subarray.
class Solution {
public:
int maxProduct(vector<int>& nums) {
int dp_max[nums.size()+1];
int dp_min[nums.size()+1];
dp_max[0] = nums[0];
dp_min[0] = nums[0];
for(int i = 1; i < nums.size(); i++){
dp_max[i] = max(dp_min[i-1]*nums[i], max(dp_max[i-1]*nums[i], nums[i]));
dp_min[i] = min(dp_min[i-1]*nums[i], min(dp_max[i-1]*nums[i], nums[i]));
}
int max_product = max(dp_max[0], dp_min[0]);
for(int i = 1; i < nums.size(); i++)
max_product = max(max_product, max(dp_max[i], dp_min[i]));
return max_product;
}
};