Why is the println() method being executed twice instead of once?

Question

public class HashMapTest2 {
    public static void main(String[] args) {
        Scanner s = new Scanner(System.in);
        System.out.println("Enter total player");
        Integer p = s.nextInt();
        System.out.println("Enter total Team");
        Integer t = s.nextInt();
        List<String> listp = new ArrayList<>();
    for (int i = 1; i<p; i++){
        System.out.println("Enter Player name "+i);
        listp.add(s.nextLine());
    }

    List<String> listt = new ArrayList<>();
    for (int i = 1; i<t; i++){
        System.out.println("Enter Team name "+i);
        listt.add(s.nextLine());
    }
    }
}

I am getting some strange outputs, like the ones below:

Enter total player
3
Enter total Team
2
Enter Player name 1
Enter Player name 2
pari
Enter Team name 1

For the first time it is asking for player's name twice and I don't know why. Any way to solve this?

Answer 1

When you are using nextInt() then the integer value is read but not the end-of-line character (Return/Enter) change your code to use nextLine() as below for correct handling.

public static void main(String... obj) {
    Scanner s = new Scanner(System.in);
    System.out.println("Enter number of Players");
    Integer p = Integer.valueOf(s.nextLine());
    System.out.println("Enter number of Teams");
    Integer t = Integer.valueOf(s.nextLine());

    List<String> listp = new ArrayList<>();
    for (int i = 0; i < p; i++){
        System.out.println("Enter Player name " + i);
        listp.add(s.nextLine());
    }
    List<String> listt = new ArrayList<>();
    for (int i = 1; i < t; i++){
        System.out.println("Enter Team name " + i);
        listt.add(s.nextLine());
    }
}