CODEWITHSUNDEEP
javarecursionprintingcharacter
erasmus77
erasmus77

Reputation: 327

Java recursive System.out.println()

package test;

import java.util.Scanner;

public class Char {
    public static void main(String[] args) {
    char c = 0;
    Scanner scan = new Scanner(System.in);
    printeaza(c, scan);
}

public static char printeaza(char c, Scanner sc) {
    c = sc.next().charAt(0);
    if (sc.hasNext()) {
        System.out.println(printeaza(c, sc));
        return c;
    } else {
        return c;
    }
}
}

What i'm trying to do is type letters from the keyboard and then have them diplayed in reverse. I know it can be made very easy with a for loop and char arrays but i'm curious about making it recursively and using only one char variable. I almost made it but it seems it prints all but the first letter.

So if I type: "a s d f" instead of "f d s a" i get only "f d s". I think I know why, it's because the Println statement it's only inside the if statement but I kind of run of ideeas about how to make the function "catch" the first letter as well. I hope you can have a look, thanks!

Upvotes: 0

Views: 1406

Answers (2)

SQB
SQB

Reputation: 4078

Your first call to printeaza(c, scan) (made from public static void main) needs to be wrapped with a System.out.println(..) as well.

Like this:

package test;

import java.util.Scanner;

public class Char {
    public static void main(String[] args) {
        char c = 0;
        Scanner scan = new Scanner(System.in);
        System.out.println(printeaza(c, sc)); // <-- changed line
    }

    public static char printeaza(char c, Scanner sc) {
        c = sc.next().charAt(0);
        if (sc.hasNext()) {
            System.out.println(printeaza(c, sc));
            return c;
        } else {
            return c;
        }
    }
}

Incorporating Cruncher's advise, I'd write it like this:

package test;

import java.util.Scanner;

public class Char {
    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        System.out.println(printeaza(sc));
    }

    public static char printeaza(Scanner sc) {
        char c = sc.next().charAt(0);
        if (sc.hasNext()) {
            System.out.println(printeaza(sc));
        } 
        return c;
    }
}

Upvotes: 3

BambooleanLogic
BambooleanLogic

Reputation: 8171

The problem is that a call to printeaza doesn't print its own character, only that of it's recursive call.

In other words, printeaza(c, scan); in main needs to be changed to System.out.println(printeaza(c, scan);

Also, I would just like to point out that using recursive calls for user input like this is not a very good idea to be honest. :/

Upvotes: 2

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