Hashset getting empty string as an element in java

Question

I am trying to add elements to hashset, but it gets an empty element into it.

Initially I tried,

import java.util.*;

public class SetTrial{

    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        int number = sc.nextInt();
        HashSet<String> names = new HashSet<String>();
        for(int j=0; j<number;j++)
        {
            String text = sc.nextLine();
            names.add(text);
        }
        System.out.println(names);
    }
}

When I give input as,

5
a
b
c
d
e

It seems to only accept input till d and execute print displaying

[, a, b, c, d]

My guess was that it is accepting a newline at beginning, so I added a sc.next() in the code.

import java.util.*;

public class SetTrial{

    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        int number = sc.nextInt();
        HashSet<String> names = new HashSet<String>();
        sc.next();
        for(int j=0; j<number;j++)
        {
            String text = sc.nextLine();
            names.add(text);
        }
        System.out.println(names);
    }
}

Although this time it seems to accept all of the input properly, the result is

[, b, c, d, e]

So the problem must be something else. How do I fix this?

The next method consumes up to whitespace (carriage return), but not the line feed. — OneCricketeer, Oct 16 '16 at 06:57

score 1 · Accepted Answer · answered Oct 16 '16 at 06:52

1

Second approach was nearly right.
Just replace sc.next() with sc.nextLine().

answered Oct 16 '16 at 06:52

Turamarth

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Hashset getting empty string as an element in java

1 Answers1