Mutable Variables

Declaring and manipulating variables in programming is a fundamental concept that allows you to store and modify data. Variables in Rust are immutable by default, but you can make them mutable using the mut keyword.

In this challenge, you will declare and use mutable variables in Rust. You will be given a function where you need to declare variables, modify their values, and perform specific operations.

Your task

Declare variable text with any initial value of type String Use let mut to make it mutable.
Re assign the variable text to something else of your choice.
Call the mutates_value(&mut text) function, which will change the value of your text variable.
Return the final value of the variable.

Hints

If you're stuck, feel free to check out the hints below

Click here to see the hints

Use the let mut keyword to declare a mutable variable.
To give the value to as a mutable reference use the &mut keyword. e.g.
```
let mut text = "hello";
mutates_value(&mut text);
```
To create a String from a &str, use String::from(value) or value.to_string(). e.g.
```
let text = "hello";
let text = text.to_string();
```

To return a value from a function, either use the return statement or let the last expression be the return value. For example:

// Using return statement
fn example1() -> String {
    return String::from("hello");
}
 
// Using expression (no semicolon)
fn example2() -> String {
    String::from("hello")
}

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Solutions

Abba Adamu

shytypes1028

4 hours ago

3.40ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    let mut text = String::from("hello");
    // 2. Call `mutates_value` with a mutable reference to `text`
      mutates_value(&mut text);
    // 3. Return the value of `text` as a String
    String::from(text)
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

Ardhi Putra

ardhptr21

4 hours ago

3.10ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    let mut text = String::from("hello");
    // 2. Call `mutates_value` with a mutable reference to `text`
    mutates_value(&mut text);
    // 3. Return the value of `text` as a String
    return text;
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

sorei9240

5 hours ago

3.82ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    let mut text: String = String::from("hello");
    // 2. Call `mutates_value` with a mutable reference to `text`
    mutates_value(&mut text);
    // 3. Return the value of `text` as a String
    return text;
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

madkrell

6 hours ago

3.46ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
let mut text: String = String::from("hello");
    // 2. Call `mutates_value` with a mutable reference to `text`
mutates_value(&mut text);
    // 3. Return the value of `text` as a String
    text
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

CASEA

Zuttergutao

16 hours ago

3.14ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    let mut text = String::from("hello");
    // 2. Call `mutates_value` with a mutable reference to `text`
    mutates_value(&mut text);
    // 3. Return the value of `text` as a String
    return text
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

Javets70

a day ago

3.91ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    let mut text = String::from("hello");
    // 2. Call `mutates_value` with a mutable reference to `text`
    let output = mutates_value(&mut text);
    // 3. Return the value of `text` as a String
    return text
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

YCH931

a day ago

3.40ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    let mut text = String::from("hello");
    // 2. Call `mutates_value` with a mutable reference to `text`
    mutates_value(&mut text);
    // 3. Return the value of `text` as a String
    text
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

Weiming

Weiming-Hu

a day ago

3.42ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    let mut text = "hello".to_string();
    // 2. Call `mutates_value` with a mutable reference to `text`
    mutates_value(&mut text);
    // 3. Return the value of `text` as a String
    return text
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

tagucci

a day ago

3.02ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    let mut text: String = "hello".to_string();
    // 2. Call `mutates_value` with a mutable reference to `text`
    mutates_value(&mut text);
    // 3. Return the value of `text` as a String
    text
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

jordan-betterman

2 days ago

2.74ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    let mut text = String::from("hello");
    // 2. Call `mutates_value` with a mutable reference to `text`
    mutates_value(&mut text);
    // 3. Return the value of `text` as a String
    return text.to_string();
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

Kağan

medarduss

2 days ago

6.00ms

81.28kb

pub fn mutating_variables() -> String {
    let mut text = String::from("hello"); // 1. Declare a mutable variable `text` with value "hello"
    mutates_value(&mut text); // 2. Call `mutates_value` with a mutable reference to `text`
    return text; // 3. Return the value of `text` as a String
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

Dezhi Zheng

MyNameLx

2 days ago

3.00ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    let mut text : String = String::from("hello");
    // 2. Call `mutates_value` with a mutable reference to `text`
    mutates_value(&mut text);
    // 3. Return the value of `text` as a String
    text
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

Dezhi Zheng

MyNameLx

2 days ago

3.11ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    let mut text : String = String::from("hello");
    // 2. Call `mutates_value` with a mutable reference to `text`
    mutates_value(&mut text);
    // 3. Return the value of `text` as a String
    text
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

Hung Dinh

nhdinh

3 days ago

3.18ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    let mut text: String = String::from("hello");
    // 2. Call `mutates_value` with a mutable reference to `text`
    mutates_value(&mut text);
    // 3. Return the value of `text` as a String
    text
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

Faharioes

3 days ago

3.38ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    let mut text: String = "hello".to_string();
    // 2. Call `mutates_value` with a mutable reference to `text`
    mutates_value(&mut text);
    // 3. Return the value of `text` as a String
    text
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

Facundo Hernandez

facuhernandez99

3 days ago

4.12ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    let mut text = String::from("hello");
    // 2. Call `mutates_value` with a mutable reference to `text`
    mutates_value(&mut text);
    // 3. Return the value of `text` as a String
    text
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

Dario d'Abate

DariodAbate

3 days ago

3.43ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    let mut text: String = "hello".to_string();
    // 2. Call `mutates_value` with a mutable reference to `text`
    mutates_value(&mut text);
    // 3. Return the value of `text` as a String
    text
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

Joshua Ball

joshball

3 days ago

3.93ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    let mut text = String::from("foo");
    // 2. Call `mutates_value` with a mutable reference to `text`
    mutates_value(&mut text);
    // 3. Return the value of `text` as a String
    text
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

skrzypson

3 days ago

3.51ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    let mut text = "text".to_string();
    // 2. Call `mutates_value` with a mutable reference to `text`
    mutates_value(&mut text);
    // 3. Return the value of `text` as a String
    text
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

Lucas Deprit

lucasdeprit

3 days ago

3.56ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    // 2. Call `mutates_value` with a mutable reference to `text`
    // 3. Return the value of `text` as a String
    let mut string: String = String::from("Hello");
    mutates_value(&mut string);
    string
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

amaneru

7ma8no9

3 days ago

3.61ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    let mut text = "hello".to_string();
    // 2. Call `mutates_value` with a mutable reference to `text`
    mutates_value(& mut text);
    // 3. Return the value of `text` as a String
    text
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

ヒヤシンス

Deathemonic

4 days ago

3.07ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    // 2. Call `mutates_value` with a mutable reference to `text`
    // 3. Return the value of `text` as a String\
    let mut text = String::from("hello");
    mutates_value(&mut text);
    return text;
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

Madhankumar Anandan

amkumar072

4 days ago

3.14ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    // 2. Call `mutates_value` with a mutable reference to `text`
    // 3. Return the value of `text` as a String
    let mut text: String = String::from("hello");
    mutates_value(&mut text);
    text
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

Joanne Muthoni

joanne-cmd

4 days ago

6.63ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
        let mut text = String::from("hello");
    // 2. Call `mutates_value` with a mutable reference to `text`
        mutates_value(&mut text);
    // 3. Return the value of `text` as a String
        text
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

EvilLary

4 days ago

3.81ms

81.28kb

pub fn mutating_variables() -> String {
    let mut text = String::from("hello");
    mutates_value(&mut text);
    text
    // 1. Declare a mutable variable `text` with value "hello"
    // 2. Call `mutates_value` with a mutable reference to `text`
    // 3. Return the value of `text` as a String
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

Pranav Garg

PranavGarg01

4 days ago

4.65ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    let mut text = String::from("hello");
    // 2. Call `mutates_value` with a mutable reference to `text`
    mutates_value(&mut text);
    // 3. Return the value of `text` as a String
    return text;
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

Muhammad Haikal

heykall

5 days ago

2.81ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    let mut text: String = "hello".to_string();
    mutates_value(&mut text);
    text
    // 2. Call `mutates_value` with a mutable reference to `text`
    // 3. Return the value of `text` as a String
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

Pedro Pelicioni

pedro-pelicioni

6 days ago

5.94ms

81.28kb

pub fn mutating_variables() -> String {
    let mut text = String::from("hello");
    mutates_value(&mut text);
    text
}
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

Ghostttty

6 days ago

5.82ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    let mut text = "hello".to_string();
    // 2. Call `mutates_value` with a mutable reference to `text`
    mutates_value(&mut text);
    // 3. Return the value of `text` as a String
    text
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

zawwwu

6 days ago

3.40ms

81.28kb

pub fn mutating_variables() -> String {
    let mut text = String::from("hello");
    mutates_value(&mut text);
    text
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

Kariss83

6 days ago

2.87ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    let mut text = "hello".to_string();
    // 2. Call `mutates_value` with a mutable reference to `text`
    mutates_value(&mut text);
    // 3. Return the value of `text` as a String
    text
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

AKA.MoneyTaker

M4Bo2

7 days ago

3.13ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
   let mut text = String::from("hello");
    // 2. Call `mutates_value` with a mutable reference to `text`
  mutates_value(&mut text);
    // 3. Return the value of `text` as a String
    text
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

Chris Anatalio

anataliocs

7 days ago

2.96ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    // 2. Call `mutates_value` with a mutable reference to `text`
    // 3. Return the value of `text` as a String
    let mut text = String::from("hello");
    mutates_value(&mut text);
    text.to_string()
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

Chris Blake

chrisb92

7 days ago

4.45ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    // 2. Call `mutates_value` with a mutable reference to `text`
    // 3. Return the value of `text` as a String
    let mut text = String::from("hello");
    mutates_value(&mut text);
    return text;
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

Yaroslav

YarRoh

7 days ago

3.84ms

81.28kb

pub fn mutating_variables() -> String {
    let mut text = String::from("Hello");
    mutates_value(&mut text);
    text
    // 1. Declare a mutable variable `text` with value "hello"
    // 2. Call `mutates_value` with a mutable reference to `text`
    // 3. Return the value of `text` as a String
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

Nelly

nellyisanon

9 days ago

3.66ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    // 2. Call `mutates_value` with a mutable reference to `text`
    // 3. Return the value of `text` as a String
    let mut text: String = "Hello".to_string();
    mutates_value(&mut text);
    text
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

JackY

Scorpio24

9 days ago

2.81ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    // 2. Call `mutates_value` with a mutable reference to `text`
    // 3. Return the value of `text` as a String
    let mut text = String::from("hello");
    mutates_value(&mut text);
    text
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

microwavestine

9 days ago

4.76ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    let mut text = "hello".to_string();
    // 2. Call `mutates_value` with a mutable reference to `text`
    mutates_value(&mut text);
    // 3. Return the value of `text` as a String
    return text;
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

Likith-LVSHD

10 days ago

3.74ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
let mut text = "hello".to_string();
    // 2. Call `mutates_value` with a mutable reference to `text`
mutates_value(&mut text);
text
    // 3. Return the value of `text` as a String
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

Likith-LVSHD

10 days ago

3.79ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
let mut text = "hello".to_string();
    // 2. Call `mutates_value` with a mutable reference to `text`
mutates_value(&mut text);
text
    // 3. Return the value of `text` as a String
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

k-tomita

k-tomita778

10 days ago

3.04ms

81.28kb

pub fn mutating_variables() -> String {
    let mut text = "hello".to_string();
    mutates_value(&mut text);
    text
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

Yi Hao

leongyihao

10 days ago

2.90ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    // 2. Call `mutates_value` with a mutable reference to `text`
    // 3. Return the value of `text` as a String
    let mut text = "hello".to_string();
    mutates_value(&mut text);
    text
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

Moseti

ENOCKMOSETI

10 days ago

3.22ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    let text = "hello";
    let mut text = text.to_string();
    // 2. Call `mutates_value` with a mutable reference to `text`
    mutates_value(&mut text);
    // 3. Return the value of `text` as a String
    return text;
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

Éric Villani

TheTrueCaligari

10 days ago

2.93ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    let mut text : String = "hello".to_string();
    // 2. Call `mutates_value` with a mutable reference to `text`
    mutates_value(&mut text);
    // 3. Return the value of `text` as a String
    text
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

fyroostr

10 days ago

4.18ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    let mut text = "hello".to_string();
    // 2. Call `mutates_value` with a mutable reference to `text`
    mutates_value(&mut text);
    // 3. Return the value of `text` as a String
    text
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

SilentCanon

silentcanon

11 days ago

2.52ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    let mut text = String::from("hello");
    // 2. Call `mutates_value` with a mutable reference to `text`
    mutates_value(&mut text);
    // 3. Return the value of `text` as a String
    return text;
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

Sabin Regmi

wheregmis

11 days ago

4.21ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    let mut text = "hello".to_string();
    // 2. Call `mutates_value` with a mutable reference to `text`
    mutates_value(&mut text);
    // 3. Return the value of `text` as a String
    text
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

xian ma

xanvcs

11 days ago

4.76ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    let mut text = String::from("hello");
    // 2. Call `mutates_value` with a mutable reference to `text`
    mutates_value(&mut text);
    // 3. Return the value of `text` as a String
    return text;
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

PixelForg

11 days ago

4.54ms

81.28kb

pub fn mutating_variables() -> String {
    let mut text = String::from("hello");
    mutates_value(&mut text);
    text
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

kustrun

11 days ago

3.04ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    // 2. Call `mutates_value` with a mutable reference to `text`
    // 3. Return the value of `text` as a String
    let mut text = String::from("hello");
    mutates_value(&mut text);
    return String::from(text);
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}