question20.java

public class question20 {

    public static int maxProduct(int[] nums) {
        if (nums == null || nums.length == 0) return 0;

        int maxProduct = nums[0];
        int minProduct = nums[0];
        int result = nums[0];

        for (int i = 1; i < nums.length; i++) {
            int current = nums[i];

            if (current < 0) {
                
                int temp = maxProduct;
                maxProduct = minProduct;
                minProduct = temp;
            }

            maxProduct = Math.max(current, current * maxProduct);
            minProduct = Math.min(current, current * minProduct);

            result = Math.max(result, maxProduct);
        }

        return result;
    }


    public static void main(String[] args) {
        int[] nums = {2, 3, -2, 4};
        System.out.println("Maximum Product Subarray: " + maxProduct(nums));  
    }
}