AP Computer Science Exam Question

public class ControlFlowQuestion {
    public static void main(String[] args) {
        int a = 5;
        int b = 3;
        
        // Determine the value of 'result' based on control flow statements
        int result;
        
        if(a > b) {
            result = a * b;
        } else if(a == b) {
            result = a + b;
        } else {
            result = a - b;
        }
        
        System.out.println("The value of result is: " + result);
    }
}

Explain and determine the output of the above code.

Answer

The given code snippet demonstrates the control flow of if-else statements. Here's the step-by-step explanation of the code and its output:

1. The code starts by declaring and initializing two integer variables, a with the value of 5, and b with the value of 3.

2. Next, an integer variable result is declared but not initialized.

3. The first control flow statement is an if statement that checks if the value of a is greater than the value of b.

4. In this case, a is indeed greater than b (5 > 3), so the code inside the if block is executed.

5. Inside the if block, the result variable is assigned the value of a * b, which is 5 * 3 = 15.

6. Since the condition of the first if statement is true, the subsequent else if and else parts of the code are skipped. Therefore, the program jumps directly to printing the value of result.

7. The last line of code outputs a message showing the value of result, which is "The value of result is: 15".

Therefore, the output of the given code will be:

The value of result is: 15

Note: If the condition of the first if statement evaluated to false, the program would have checked the condition of the else if statement. If that were also false, the program would enter the else block.