We use cookies to ensure you have the best browsing experience on our website. Please read our cookie policy for more information about how we use cookies.
  1. Prepare
  2. Java
  3. Data Structures
  4. Java Map
  5. Discussions

Java Map

Sort by

recency

|

377 Discussions

|

  • Damian_GDO_92
     + 0 comments
    //Complete this code or write your own from scratch
import java.util.*;
import java.io.*;

class Solution{
	public static void main(String []argh)
	{
		Scanner in = new Scanner(System.in);
        
		int n = in.nextInt();
        
        if (n < 0 || n > 100000) {
            throw new IllegalArgumentException("The number of people-phones cannot be lower than 0 or greater than 100,000");
        }
		
        Map<String, Integer> phoneBook = new HashMap<>();
        
        in.nextLine();
        
		for(int i=0; i<n; i++) {
			String name = in.nextLine().toLowerCase();
			Integer phone = in.nextInt();
            in.nextLine();
			
            if (String.valueOf(phone).length() != 8) {
                throw new IllegalArgumentException(String.format("The phone number %s is not 8 digits long", phone));
            }
            
            phoneBook.put(name, phone);
		}
        
		while(in.hasNext()) {
			String s = in.nextLine().toLowerCase();
            
            Integer phone = phoneBook.get(s);
            
            if (phone == null) {
                System.out.println("Not found");
            } else {
                System.out.println(String.format("%s=%d", s, phone));
            }
		}
	}
}

  • yashdeora98294
     + 0 comments

    Here is Java Map solution - https://programmingoneonone.com/hackerrank-java-map-problem-solution.html

  • navamsharma142
     + 1 comment

    I don't understand the sample testcase. Tom clearly has a phone number why the output is not found??

  • rjrosa
     + 0 comments
    Scanner scanner = new Scanner(System.in);
        Map<String, String> phone = new HashMap<>();
        int n = scanner.nextInt();
        scanner.nextLine(); // consume newline after reading int

        for (int i = 0; i < n; i++) {
            String name = scanner.nextLine();
            String number = scanner.nextLine();
            phone.put(name, number);
        }

        while (scanner.hasNextLine()) {
            String qr = scanner.nextLine();
            if (phone.containsKey(qr)) {
                System.out.println(qr + "=" + phone.get(qr));
            } else {
                System.out.println("Not found");
            }
        }

        scanner.close();

  • Dilrangi
     + 0 comments
    public static void main(String[] args) throws IOException {
    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

    int n = Integer.parseInt(br.readLine().trim());
    Map<String, Integer> phoneBook = new HashMap<>();

    for(int i=0; i<n; i++){
        String name = br.readLine().trim();
        int phoneNumber = Integer.parseInt(br.readLine().trim());
        phoneBook.put(name, phoneNumber);
    }

    String query;
    StringBuilder sb = new StringBuilder();
    while((query = br.readLine())!=null && !query.isEmpty()){
        if(phoneBook.containsKey(query)){
            sb.append(query+"="+phoneBook.get(query)).append("\n");
        } else{
            sb.append("Not found\n");
        }
    }
    System.out.println(sb.toString().trim());
}

    }