子数组最大乘积

/**
 *
 * @param arr double浮点型一维数组
 * @param arrLen int arr数组长度
 * @return double浮点型
 */
double GetMax(double x1,double x2,double x3)
{
    double maxx = x1;
    if(maxx < x2) maxx = x2;
    if(maxx < x3) maxx = x3;
    return maxx;
}
double GetMin(double x1,double x2,double x3)
{
    double minx = x1;
    if(minx > x2) minx = x2;
    if(minx > x3) minx = x3;
    return minx;
}
double maxProduct(double* arr, int arrLen ) {
    // write code here
    if(0 == arrLen) return 0;
    double *maxa = (double*)malloc(arrLen*sizeof(double));
    double *mina = (double*)malloc(arrLen*sizeof(double));
    memset(maxa, 0, arrLen);
    memset(mina, 0, arrLen);
    maxa[0] = arr[0];
    mina[0] = arr[0];
   
   
    for(int i = 1; i < arrLen; i++)
    {
       
            maxa[i] = GetMax(arr[i], maxa[i-1]*arr[i], mina[i-1]*arr[i]);
            mina[i] = GetMin(arr[i], maxa[i-1]*arr[i], mina[i-1]*arr[i]);
       
    }
    double res = maxa[0];
    for(int i = 0; i < arrLen; i++)
    {
        if(res < maxa[i]) res = maxa[i];
    }
    return res;
}