Do–while loop in Javascript - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to run the loop body at least once.

Javascript

let count = 0;
do {
  console.log(count);
  count++;
} while ([1]);

Drag options to blanks, or click blank then click option'

Acount = 3

Bcount < 3

Ccount++

Dcount > 3

Attempts:

3 left

💡 Hint

Common Mistakes

Using assignment (=) instead of comparison (== or <).

Using increment (count++) in the condition.

The do-while loop runs the code block first, then checks the condition. The condition count < 3 ensures the loop runs while count is less than 3.

2fill in blank

medium

Complete the code to print numbers from 1 to 5 using a do–while loop.

Javascript

let num = 1;
do {
  console.log(num);
  num++;
} while ([1]);

Drag options to blanks, or click blank then click option'

Anum <= 5

Bnum < 5

Cnum == 5

Dnum > 5

Attempts:

3 left

💡 Hint

Common Mistakes

Using num < 5 which stops before printing 5.

Using equality num == 5 which runs only once.

The loop should continue while num is less than or equal to 5 to print numbers 1 through 5.

3fill in blank

hard

Fix the error in the do–while loop condition to avoid an infinite loop.

Javascript

let i = 0;
do {
  console.log(i);
  i++;
} while ([1]);

Drag options to blanks, or click blank then click option'

Ai > 3

Bi = 3

Ci++ < 3

Di < 3

Attempts:

3 left

💡 Hint

Common Mistakes

Using assignment (=) instead of comparison (== or <).

Putting increment (i++) inside the condition.

The condition i < 3 correctly checks if i is less than 3. Using i = 3 assigns 3 and causes an infinite loop.

4fill in blank

hard

Fill both blanks to create a do–while loop that prints even numbers from 2 to 10.

Javascript

let n = [1];
do {
  console.log(n);
  n [2] 2;
} while (n <= 10);

Drag options to blanks, or click blank then click option'

A2

B+=

C-=

D0

Attempts:

3 left

💡 Hint

Common Mistakes

Starting at 0 instead of 2.

Using subtraction instead of addition.

Start n at 2 and increase it by 2 each loop using += to print even numbers up to 10.

5fill in blank

hard

Fill all three blanks to create a do–while loop that counts down from 5 to 1.

Javascript

let x = [1];
do {
  console.log(x);
  x [2] 1;
} while (x [3] 0);

Drag options to blanks, or click blank then click option'

A5

B-=

C>

D<

Attempts:

3 left

💡 Hint

Common Mistakes

Using addition instead of subtraction.

Using less than comparison which would cause an infinite loop.

Start x at 5, subtract 1 each time, and continue while x is greater than 0 to count down.