Day 28: RegEx, Patterns, and Intro to Databases Hackerrank Solution Java

 Day 28: RegEx, Patterns, and Intro to Databases 

For Explanation Check Video:

Sample Input

6
riya riya@gmail.com
julia julia@julia.me
julia sjulia@gmail.com
julia julia@gmail.com
samantha samantha@gmail.com
tanya tanya@gmail.com

Sample Output

julia
julia
riya
samantha
tanya

Code:

import java.io.*;
import java.math.*;
import java.security.*;
import java.text.*;
import java.util.*;
import java.util.concurrent.*;
import java.util.regex.*;
public class Solution {


    private static final Scanner scanner = new Scanner(System.in);
    public static void main(String[] args) {
        int N = scanner.nextInt();
        scanner.skip("(\r\n|[\n\r\u2028\u2029\u0085])?");
        String reg = ".+@gmail\\.com$";
        Pattern p = Pattern.compile(reg);
        ArrayList<String> al = new ArrayList<>();
        for (int NItr = 0; NItr < N; NItr++) {
            String[] firstNameEmailID = scanner.nextLine().split(" ");
            String firstName = firstNameEmailID[0];
            String emailID = firstNameEmailID[1];
            Matcher m = p.matcher(emailID);
            if(m.find()){
                al.add(firstName);
            }
        }
        Collections.sort(al);
        for(String s:al){
            System.out.println(s);
        }
        scanner.close();
    }
}