Based on the dangling-else discussion in Exercise 4.27, state the output for each of the following code segments when x is 9 and y is 11 and when x is 11 and y is 9. We eliminated the indentation from the following code to make the problem more chal- lenging. Apply the indentation conventions you’ve learned.

a)
    if (x < 10)
    if (y > 10)
    System.out.println("*****");
    else
    System.out.println("#####");
    System.out.println("$$$$$");
b)

    if (x < 10) {
    if (y > 10)
    System.out.println("*****");
    }
    else {
    System.out.println("#####");
    System.out.println("$$$$$");
    }

Exercise 4.27

The Java compiler always associates an else with the immediate- ly preceding if unless told to do otherwise by the placement of braces ({ and }). This behavior can lead to what is referred to as the dangling-else problem. The indentation of the nested statement

    if (x > 5)
    if (y > 5)
    System.out.println("x and y are > 5");
    else
    System.out.println("x is <= 5");

appears to indicate that if x is greater than 5, the nested if statement determines whether y is also greater than 5. If so, the statement outputs the string "x and y are > 5". Otherwise, it appears that if x is not greater than 5, the else part of the if…else outputs the string "x is <= 5". Beware! This nested if…else statement does not execute as it appears. The compiler actually interprets the statement as

    if (x > 5)
    if (y > 5)
    System.out.println("x and y are > 5");
    else
    System.out.println("x is <= 5");

in which the body of the first if is a nested if…else. The outer if statement tests whether x is greater than 5. If so, execution continues by testing whether y is also greater than 5. If the second condition is true, the proper string—"x and y are > 5"—is displayed. However, if the second con- dition is false, the string "x is <= 5" is displayed, even though we know that x is greater than 5. Equally bad, if the outer if statement’s condition is false, the inner if…else is skipped and noth- ing is displayed. For this exercise, add braces to the preceding code snippet to force the nested if…else statement to execute as it was originally intended.