题解 | #乘积为正数的最长连续子数组#

import java.util.Scanner;

// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int len = sc.nextInt();
        int[] nums = new int[len];
        for(int i = 0; i < len; i++) {
            nums[i] = sc.nextInt();
        }
        //到下标i为止的乘积为正数的最长子数组长度
        int[] positive = new int[len];
        //到下标i为止的乘积为负数的最长子数组长度
        int[] negitive = new int[len];
        if(nums[0] > 0) {
            positive[0] = 1;
        }else if(nums[0] < 0) {
            negitive[0] = 1;
        }
        int res = positive[0];//初始化别出错
        for(int i = 1; i < len; i++) {
            if(nums[i] > 0) {
                positive[i] = positive[i - 1] + 1;
                negitive[i] = (negitive[i - 1] == 0) ? 0 : negitive[i - 1] + 1;
            }else if(nums[i] < 0) {
                positive[i] = (negitive[i - 1] == 0) ? 0 : negitive[i - 1] + 1;
                negitive[i] = positive[i - 1] + 1;
            }else if(nums[i] == 0) {
                positive[i] = 0;
                negitive[i] = 0;
            }
            res = Math.max(res, positive[i]);
        }
        System.out.println(res);
    }
}