Hackerrank Java End-of-file Solution

"In computing, End Of File (commonly abbreviated EOF) is a condition in a computer operating system where no more data can be read from a data source." — (Wikipedia: End-of-file)

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 in java8

Approach 1.

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Approach 2.

import java.io.*;
import java.util.*;

public class Solution {

    public static void main(String[] args) {
        Scanner sc=new Scanner(System.in);  
        int i = 0;
        while (sc.hasNextLine()) {
            System.out.println(++i + " " + sc.nextLine());
        }
    }
}

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Approach 3.

import java.io.*;
import java.util.*;

public class Solution {

    public static void main(String[] args) {
        /* Enter your code here. Read input from STDIN. Print output to STDOUT. Your class should be named Solution. */
        Scanner scanner = new Scanner(System.in);
        
        for(int i =1; scanner.hasNext(); i++){
            System.out.println(i+" "+scanner.nextLine());
        }
    }
}

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