The challenge here is to read lines of input until you reach EOF, then number and print all lines of content.

 Hint: Java's Scanner.hasNext() method is helpful for this problem.

Input Format

Read some unknown  lines of input from stdin(System.in) until you reach EOF; each line of input contains a non-empty String.

Output Format

For each line, print the line number, followed by a single space, and then the line content received as input.

Sample Input

Hello world
I am a file
Read me until end-of-file.

Sample Output

1 Hello world
2 I am a file
3 Read me until end-of-file.

Solution:

import java.io.*;
import java.util.*;
public class Solution {
    public static void main(String[] args) {
          Scanner scanner = new Scanner(System.in);
        
        int lineNumber = 1;
        
        // Read input until EOF
        while (scanner.hasNext()) {
            String line = scanner.nextLine();  // Read the next line of input
            System.out.println(lineNumber + " " + line);  // Print the line number followed by the line content
            lineNumber++;  // Increment the line number
        }
        
        scanner.close();
    }
}