Problem:
Problem Statement

You are given two integers a and b (a≤b). Determine if the product of the integers a, a+1, …, b is positive, negative or zero.

Constraints

a and b are integers.

-10^9≤a≤b≤10^9

Partial Score

In test cases worth 100 points, -10≤a≤b≤10.

Input

The input is given from Standard Input in the following format:

a b

Output

If the product is positive, print Positive. If it is negative, print Negative. If it is zero, print Zero.

Sample Input 1

1 3

Sample Output 1

Positive

1×2×3=6 is positive.

Sample Input 2

-3 -1

Sample Output 2

Negative

(-3)×(-2)×(-1)=-6 is negative.

Sample Input 3

-1 1

Sample Output 3

Zero

(-1)×0×1=0.

Solution in C# (.NET Core 3.1.201) (judge verdict: Accepted)

using System;
using System.IO;
using System.Text;

class Program
{
    static void Main(string[] args) {
        var scan = new Scanner();
        var writer = new StreamWriter(Console.OpenStandardOutput()) {AutoFlush = false};
        Console.SetOut(writer);
        Console.WriteLine(Solve(scan));
        Console.Out.Flush();
    }
    static object Solve(Scanner scan) {
        long a = scan.NextLong(), b = scan.NextLong();
        if (a == 0 || b == 0 || a < 0 && 0 < b) return "Zero";
        if (a < 0 && b < 0) {
            return (Math.Abs(a - b) + 1) % 2 == 0 ? "Positive" : "Negative";
        }
        return "Positive";
    }
}

class Scanner
{
    string[] s;
    int i;
    public Scanner() {
        s = new string[0];
        i = 0;
    }
    public string Next() {
        if (i < s.Length) return s[i++];
        string str = Console.ReadLine();
        while (str == "") str = Console.ReadLine();
        s = str.Split(' ', StringSplitOptions.RemoveEmptyEntries);
        if (s.Length == 0) return Next();
        i = 0;
        return s[i++];
    }
    public long NextLong() => long.Parse(Next());
}