"Bubble Gum"

Similar problems can happen when a student tries to use a while instead of an if:

public void isItNegative(int num) {
  while (num < 0) {
    System.out.println(num + " is negative");
    num = -num;
  }
}

Such code often will not compile (even if it did, zero is not really handled right):

public void whichIsIt(int num) {
  while (num < 0) {
    System.out.println(num + " is negative");
  } else {
    System.out.println(num + " is positive");
  }
}

Ideas for improvement
- Emphasize simplicity
  - Students should be encouraged to simplify a correct solution that is excessively complex
  - A shorter, simpler solution to a problem is also less likely to have bugs
  - Tell students that simplifying their code is a good way to find and eliminate bugs that they fail to find when testing
- Clarify that "if" is about a single decision; "while" is about a sequence of decisions. Students confuse them because they both use conditions.

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