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Even or Odd Number

beginner Number Problems

Read one integer and print Even if it is divisible by 2, otherwise print Odd. The number can be negative or zero.

Constraints

-10^9 <= n <= 10^9

Examples

Input

Output

Even

Input

Output

Odd

Remainder operator %
Negative numbers and %

Solutions

Best approachTime O(1)Space O(1)

A number is even when it divides by 2 with no remainder. For negative numbers Java, JavaScript and TypeScript give a negative remainder (-3 % 2 = -1), so the safe test is remainder == 0.

Same code works in Java810172125Basic features only, so nothing changes between versions.

/*
 * Problem : Check if a number is even or odd.
 * Input   : One integer.
 * Output  : Even or Odd.
 * Approach: Check the remainder when dividing by 2.
 * Time    : O(1)
 * Space   : O(1)
 * Java    : 8 or newer.
 */
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        int number = new Scanner(System.in).nextInt();

        // Step 1: Find the remainder when the number is divided by 2.
        int remainder = number % 2;

        // Step 2: Even numbers have remainder 0. Odd numbers have remainder 1 or -1.
        // In Java, -3 % 2 is -1, so we compare with 0 and not with 1.
        if (remainder == 0) {
            System.out.println("Even");
        } else {
            System.out.println("Odd");
        }
    }
}

Hints (2)

Use the % operator.
Do not test remainder == 1: it fails for negative odd numbers in Java.