TemporaryProblem

package com.example.app;

public class ExampleApp {

    public static void main(String[] args){
        int n;
        Scanner in = new Scanner(System.in);
        n = in.read();
        System.out.println(myFunc(n));
    }

    public String myFunc(int border) {
        int temp = 0;
        String s = "";
        if (temp<border){
            s = s + temp.toString() + " ";
            myFunc(temp+1);
        } elseif (temp==border) {
            return s;
        }
        return null;
    }
}