求一个数组中连续子数组的最大乘积

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

        if (nums.length == 1) {
            return nums[0];
        }

        int tempMax = 0;
        int tempMin = 0;
        int max = 0;

        for (int num : nums) {
            if (num > 0) {
                tempMax = Math.max(tempMax * num, num);
                tempMin = Math.min(tempMin * num, num);
            } else if (num < 0) {
                int temp = tempMax;
                tempMax = Math.max(tempMin * num, num);
                tempMin = Math.min(temp * num, num);
            } else {
                tempMin = tempMax = 0;
            }

            if (tempMax > max) {
                max = tempMax;
            }
        }
        return max;
    }

    public int maxProduct2(int[] nums) {
        if (nums == null || nums.length == 0) {
            return 0;
        }
        if (nums.length == 1) {
            return nums[0];
        }

        int max = nums[0], min = nums[0], result = nums[0];
        for (int i = 1; i < nums.length; i++) {
            int mx = max;
            int mn = min;
            max = Math.max(Math.max(mx * nums[i], mn * nums[i]), nums[i]);
            min = Math.min(Math.min(mx * nums[i], mn * nums[i]), nums[i]);
            if (max > result) {
                result = max;
            }
        }
        return result;

    }

    public static void main(String[] args) {
        int[] nums = {-2, 1, 4, 0, 9, 3};
        int result = new Solution().maxProduct(nums);
        System.out.println(result);
    }
}

[参考]http://blog.csdn.net/worldwindjp/article/details/39826823

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