Question

Say Karel is on a location with one tennis ball. After the following code runs, how many tennis balls will there be at that location?

for (var i = 0; i < 3; i++) {
if (ballsPresent()) {
takeBall();
} else {
putBall();
putBall();
}
}
JavaScript


0


1


2


6

Answer 1

are you sure

Answer 2

so is it a b c or d

Answer 3

The correct answer is 2.

Explanation:

- The loop will run 3 times, since the condition `i < 3` is true for `i` values 0, 1, 2.
- If there is a tennis ball present (`ballsPresent()` returns true), Karel will take the ball using the `takeBall()` command.
- If there is no tennis ball present, Karel will put two tennis balls at the location using the `putBall()` command twice.

In total, the conditional statements will only run once, when `i` is 0 and there is no tennis ball present. Therefore, Karel will put two tennis balls at the location during this iteration.

After all 3 iterations of the loop, Karel will have put a total of 2 tennis balls at the location.

Answer 4

Apologies for the incorrect response.

The correct answer is 1.

Explanation:

The loop will run 3 times as `i < 3`. During the first iteration, Karel will check if there is a tennis ball present. If there is, Karel will take the ball using `takeBall()`. If there isn't a ball present, Karel will put two balls at the location using `putBall()` twice.

In this case, since Karel initially has 1 tennis ball, `ballsPresent()` will return true during the first iteration and Karel will take the ball. Therefore, after the code runs, there will be no tennis balls at the location, resulting in 0 tennis balls.

Answer 5

I apologize for the confusion. The correct answer is B. After the code runs, there will be 1 tennis ball at the location. This is because during the first iteration of the loop, `ballsPresent()` returns true (since Karel has initially 1 tennis ball) and Karel will take the ball using `takeBall()`. As a result, the location will have 1 tennis ball at the end.