Need little help on understanding how starting index and substring works

Question

Here is my code

public static void main(String[] args) {
    Scanner reader = new Scanner(System.in);

    System.out.print("Type a word: ");
    String userWord = reader.nextLine();

    System.out.print("Length of the first part: ");
    int userLength = Integer.parseInt(reader.nextLine());

    System.out.println("Result: " + userWord.substring(0, userLength));
}

Result:

Type a word: hellothere
Length of the first part: 3
Result: hel

Starting index starts counting from 0 right? So shouldn't the result print "hell"?

0 = h

1 = e

2 = l

3 = l

"The substring begins at the specified `beginIndex` and extends to the character at index `endIndex - 1`" — byxor, Jun 27 '17 at 12:10
https://docs.oracle.com/javase/8/docs/api/java/lang/String.html#substring-int-int- — JB Nizet, Jun 27 '17 at 12:10

score 0 · Accepted Answer · answered Jun 27 '17 at 12:13

0

The second parameter of substring() is an exlusive index. Means: When you enter 3 it will give you only the letters until index 2. This isn't one of the most obvious methods in the Java API, but should be well documented.

answered Jun 27 '17 at 12:13

Florian S.

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Need little help on understanding how starting index and substring works

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