Safe Parsing

Lab Java Beginner 10 points

Read n tokens. For each print the number doubled, or invalid: TOKEN if it isn't an integer (catch NumberFormatException).

Input

n, then n tokens.

Output

n lines.

Example

Input

4
5
abc
-3
2.5

Output

10
invalid: abc
-6
invalid: 2.5

Sample input available Sample output available

Editor

Java

Hints

Integer.parseInt throws NumberFormatException for bad text.

Solution explanation

Catching a specific exception type handles the expected failure and lets real bugs surface.

Show solution

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        for (int i = 0; i < n; i++) {
            String token = sc.next();
            try {
                System.out.println(Integer.parseInt(token) * 2);
            } catch (NumberFormatException e) {
                System.out.println("invalid: " + token);
            }
        }
    }
}

Output

Answer