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.
• 最大子串的乘积，主要是用到了动态规划的算法。C++ Code 如下：

class Solution {
public:
    int maxProduct(int a[], int n) {
    int *max = new int[n];
    int *min = new int[n];

    max[0] = a[0];
    min[0] = a[0];

    int product = max[0];

    for (int i=1; i<n; i++)
    {
        max[i] = MaxinThree(a[i], a[i]*max[i-1], a[i]*min[i-1]);  
        min[i] = MininThree(a[i], a[i]*max[i-1], a[i]*min[i-1]);   

        if (max[i] > product)
            product = max[i];
    }

    delete [] max;
    delete [] min;

    return product;


    }

    int MaxinThree(int num1, int num2, int num3)
    {
        int temp = num1 > num2 ? num1 : num2;
        return temp > num3 ? temp: num3;
    }

    int MininThree(int num1, int num2, int num3)
    {
        int temp = num1 < num2 ? num1 : num2;
        return temp < num3 ? temp: num3;
    }



};