Control Flow - Quiz

Choose the correct method to check if an age allows entry when using an if statement condition.

Complete the switch statement to handle all unmatched values with a default branch.

Select the correct keyword to immediately exit a for loop when a match is found.

Which control flow construct is most appropriate for choosing one of many constant integer options such as menu selections 1-5?

You need to validate user age and apply different discounts for age <18, 18-64, and 65+. What structure best fits this?

Which loop is best when you must execute a block at least once, then repeat while a condition stays true?

You must process each element of an int[] without modifying the array or using indices. What is the most concise option?

In a while loop that reads user input until "quit" is entered, what is the main risk if you forget to update the input variable inside the loop?

In a nested for loop over rows and columns, which statement lets you skip only the rest of the current inner loop iteration when a cell is empty?

What happens if you omit break in a non-last case of a switch statement?

You want to exit both inner and outer loops when a value is found in a matrix. Which feature helps you target the outer loop directly?

Which loop construct automatically stops once it has visited each element in a List<String>?

Where can a label be applied in Java to use with break or continue?

Order the steps to read commands in a loop until the user types "exit" using a while loop.

Drag and drop to reorder, or use the arrows.

Order the steps to search a 2D array and stop both loops when a target is found using a labeled break.

Drag and drop to reorder, or use the arrows.

What is the output of this conditional discount logic?

1int price = 100;
2int age = 70;
3if (age >= 65) {
4    price -= 20;
5} else if (age >= 18) {
6    price -= 10;
7} else {
8    price -= 5;
9}
10System.out.println(price);

What does this switch statement print for the given day code?

1int dayCode = 6;
2String type;
3switch (dayCode) {
4    case 1:
5    case 7:
6        type = "Weekend";
7        break;
8    case 2:
9    case 3:
10    case 4:
11    case 5:
12    case 6:
13        type = "Weekday";
14        break;
15    default:
16        type = "Invalid";
17}
18System.out.println(type);

What is printed after this for loop with continue?

1int sum = 0;
2for (int i = 1; i <= 5; i++) {
3    if (i % 2 == 0) {
4        continue;
5    }
6    sum += i;
7}
8System.out.println(sum);

Predict the output of this do-while loop that validates a counter.

1int count = 3;
2int printed = 0;
3do {
4    printed++;
5    count--;
6} while (count > 3);
7System.out.println(printed);

What is the single line of output of the enhanced for loop with break?

1int[] values = {2, 4, 6, 8};
2int found = -1;
3for (int v : values) {
4    if (v > 5) {
5        found = v;
6        break;
7    }
8}
9System.out.println(found);

Find the bug in this while loop that reads until "stop" is entered.

Click on the line(s) that contain the bug.

Scanner scanner = new Scanner(System.in);

String cmd = scanner.nextLine();

while (!cmd.equalsIgnoreCase("stop")) {

    System.out.println("Command: " + cmd);

}

scanner.close();

Identify the bug in this enhanced for loop that tries to skip negative scores.

Click on the line(s) that contain the bug.

int[] scores = {10, -1, 20};

for (int s : scores) {

    if (s < 0)

        break;

    System.out.println("Valid: " + s);

}

Match each control flow construct with its best description.

Click an item on the left, then click its match on the right. Click a matched item to unmatch.

Match each keyword with how it affects loop execution.

Click an item on the left, then click its match on the right. Click a matched item to unmatch.

Complete the code to iterate over an array of tasks and stop the loop when a "DONE" marker is found.

Fill in the blanks to repeatedly prompt for a PIN using a do-while loop until the correct value is entered.

Complete the while loop that sums positive numbers in an array using an index.

Complete the switch statement that categorizes a status code, using a default branch for unknown values.

Click the line that causes only the inner loop to exit when a zero is found.

Click on the line to select.

int[][] grid = {{1, 2}, {3, 0}};

outer: for (int i = 0; i < grid.length; i++) {

    for (int j = 0; j < grid[i].length; j++) {

        if (grid[i][j] == 0) {

            break;

        }

    }

}

System.out.println("Done");

Click the line where a labeled continue sends control to the next iteration of the outer loop.

Click on the line to select.

outer: for (int i = 0; i < 3; i++) {

    for (int j = 0; j < 3; j++) {

        if (j > i) {

            continue outer;

        }

    }

}

System.out.println("Finished");