Java puzzle 19: Overloading methods

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If this code is compiled and run, it writes null3 to the standard output. Write only one statement at line 9. As a result of that statement the output of the program becomes x5.
What is that statement?

Java puzzle 19: Overloading methods

Level: Normal

public class MyClass
  String s;
  int i;
  public void meth()
    i += 3;
    // add your statement here!
    System.out.print(s + i);
  public void meth(String s, int i)
    this.s = s;
    this.i += i;
  public static void main(String[] args)
    MyClass mc = new MyClass();

Author: Sar Maroof

Answer explanation

  1. To solve this puzzle we need to reassign the instance variables str and i.
  2. To do that with only one statement we need to use the method myMethod with two parameters.
    if we pass the parameters x and 5, the output becomes x8, because the statement i += 3; increments the value of i by 3.
    Therefore we pass the parameters x and 2 to the method as follows.
    The correct answer is:  meth(“x”, 2);

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Sar Maroof is graduated from HBO Amsterdam "higher professional education". He is a professional computer programming teacher, gives master classes and publishes technical articles. His experience with developing software started from 2001 and he has worked as a software developer for several big as well as small companies and later as a freelancer. He is the author of Java quizmaster and Build a Java application in 7 days.

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