While loop in Rust - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a while loop that counts down from 3 to 1.

Rust

let mut count = 3;
while [1] {
    println!("{}", count);
    count -= 1;
}

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

Acount >= 5

Bcount < 0

Ccount == 0

Dcount > 0

Attempts:

3 left

💡 Hint

Common Mistakes

Using a condition that never becomes false, causing an infinite loop.

Using count == 0 which stops the loop immediately.

The condition count > 0 keeps the loop running while count is positive, counting down from 3 to 1.

2fill in blank

medium

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

Rust

let mut num = 1;
while [1] {
    println!("{}", num);
    num += 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 num == 5 which runs only once.

The condition num <= 5 ensures the loop prints numbers 1 through 5 inclusive.

3fill in blank

hard

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

Rust

let mut x = 0;
while [1] {
    println!("{}", x);
    x += 1;
    if x == 3 {
        break;
    }
}

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

Ax < 3

Bx > 3

Ctrue

Dx == 0

Attempts:

3 left

💡 Hint

Common Mistakes

Using a condition that never becomes false without a break causes infinite loop.

Using x < 3 would also work but the task asks to fix the error with break.

Using true creates an infinite loop, but the break statement stops it when x == 3.

4fill in blank

hard

Fill both blanks to create a while loop that prints even numbers less than 10.

Rust

let mut n = 0;
while [1] {
    println!("{}", n);
    n [2] 2;
}

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

An < 10

Bn <= 10

C+=

D-=

Attempts:

3 left

💡 Hint

Common Mistakes

Using <= 10 includes 10 which is not less than 10.

Using -= 2 decreases n causing an infinite loop.

The loop runs while n < 10 and increments n by 2 each time to print even numbers.

5fill in blank

hard

Fill all three blanks to create a while loop that collects numbers less than 5 into a vector.

Rust

let mut v = Vec::new();
let mut i = 0;
while [1] {
    v.push([2]);
    i [3] 1;
}

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

Ai < 5

Bi

C+=

Dv.len() < 5

Attempts:

3 left

💡 Hint

Common Mistakes

Using v.len() < 5 in the condition can cause confusion.

Forgetting to increment i causes an infinite loop.

The loop runs while i < 5, pushes i into the vector, and increments i by 1 each time.