Maximum Product Subarray

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.

 

 1 public class Solution {

 2     public int maxProduct(int[] A) {

 3         if(A == null || A.length == 0) return 0;

 4         int result = A[0]; 

 5         int max = A[0];

 6         int min = A[0];

 7         for(int i = 1; i < A.length; i ++){

 8             int first = A[i] * max;

 9             int second= A[i] * min;

10             max = Math.max(Math.max(first, second), A[i]);

11             min = Math.min(Math.min(first, second), A[i]);

12             result = Math.max(result, max);

13         }

14         return result;

15     }

16 }