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 PHP7 (7.0.15) (judge verdict: Accepted)

<?php
list($a, $b) = explode(" ", trim(fgets(STDIN)));

if (0 < $a) {
    echo 'Positive';
} elseif ($a * $b <= 0){
    echo 'Zero';
} else {
    if(($b - $a + 1) % 2 == 1 || $a == $b){
        echo 'Negative';
    } else {
        echo 'Positive';
    }
}