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 an 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

Hari haran

hariFED

30 minutes ago

2.87ms

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")
}

It5Duck

an hour ago

3.30ms

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")
}

CharlieBrown1-2

4 hours ago

2.70ms

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")
}

Faruk

aafeke

5 hours ago

2.67ms

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")
}

natheumowitz-code

6 hours ago

3.70ms

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")
}

Matt Oldham

matt-o-zetland

10 hours ago

3.01ms

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")
}

Camden

CamdenForbes

a day ago

3.01ms

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")
}

Omxd147

a day ago

2.91ms

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`
    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")
}

Xavier Travers

DigitalData

a day ago

3.24ms

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")
}

m0rnin

a day ago

2.90ms

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")
}

alexsmith82

a day ago

2.84ms

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

mwheeleraus

a day ago

2.91ms

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")
}

Abeautifulsnow

a day ago

2.85ms

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")
}

learning-me

2 days ago

3.90ms

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")
}

Monsler

2 days ago

2.83ms

81.28kb

pub fn mutating_variables() -> 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")
}

Martin He

martin-he543

2 days ago

2.93ms

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")
}

Hariom

om-secadvice

3 days ago

2.83ms

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")
}

Harikrishnan B

harihkim

3 days ago

2.85ms

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")
}

Igor Kovacevic

ikovacevic

3 days ago

3.75ms

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")
}

brubsby

3 days ago

3.00ms

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")
}

Zorah

ZorahScope

3 days ago

2.93ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    let mut text = String::from("");
    // 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")
}

Islam Elsayed

Elsayed91

3 days ago

3.58ms

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")
}

Loki

Loki-101

4 days ago

2.97ms

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

Hussein Aprianto

HusseinHato

4 days ago

2.76ms

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

Piotr Baranowski

piotrbar250

4 days ago

3.65ms

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")
}

Taufiq Hisyam

ozmydas

4 days ago

3.56ms

81.28kb

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

Taufiq Hisyam

ozmydas

4 days ago

3.48ms

81.28kb

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

Ivo Kovac

kovacivo

4 days ago

3.01ms

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.to_string()
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

M1NDB3ND3R

Tharun-DV

4 days ago

2.77ms

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")
}

jstickn

4 days ago

3.19ms

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")
}

lavapool

wpoolw

4 days ago

3.04ms

81.28kb

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

khadre07

4 days ago

3.83ms

81.28kb

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

T4D4

T4D4-IU

4 days ago

3.36ms

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.to_string()
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

Kourosh Mozafari

kmozafari

4 days ago

3.87ms

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")
}

Kcyg

4 days ago

2.70ms

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")
}

BasnetModick

5 days ago

2.91ms

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")
}

Sukemcute

5 days ago

3.45ms

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);
    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")
}

Nguyễn Trọng Khôi

trongkhoidev

5 days ago

2.82ms

81.28kb

pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"
    let mut text :String = String ::from ("hello");
    mutates_value(&mut text);
    return 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")
}

azmahflameheart

5 days ago

3.22ms

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")
}

NAULINALBAN

5 days ago

2.70ms

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")
}

masterdpro0

5 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;
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

PreppyMiguel

lusuo9

5 days ago

3.04ms

81.28kb

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

Ayoola Oluwafemi

Osuolale1

5 days 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
    text.to_string()
}
// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}

Álex Frías

alexwebdev05

5 days ago

2.62ms

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")
}

Amlezia

5 days ago

3.01ms

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

Agon Dise

AgonDise

5 days ago

2.80ms

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")
}

Eliettetheegeek

5 days ago

3.45ms

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")
}

emiludenz

5 days ago

2.92ms

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

GluconFix

gluconfix

6 days ago

2.83ms

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")
}

LawisChen

6 days ago

2.91ms

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")
}