Rust Function: Reverse a string

Last update on December 21 2024 10:21:01 (UTC/GMT +8 hours)

Write a Rust function that takes a string and returns the reverse of the string.

Sample Solution:

Rust Code:

// Define a function named 'reverse_string' that takes a string as input and returns its reverse
fn reverse_string(input: &str) -> String {
    // Create a new String to store the reversed string
    let mut reversed_string = String::new();

    // Iterate over the characters of the input string in reverse order
    for c in input.chars().rev() {
        reversed_string.push(c); // Append each character to the reversed string
    }

    reversed_string // Return the reversed string
}

fn main() {
    let input_string = "hello"; // Define the input string

    // Call the 'reverse_string' function with the input string and store the result
    let reversed = reverse_string(input_string);

    // Print the reversed string
    println!("Original string: {}", input_string);
    println!("Reversed string: {}", reversed);
}

Output:

Original string: hello
Reversed string: olleh

Explanation:

Here's a brief explanation of the above Rust code:

'fn reverse_string(input: &str) -> String { ... }': This is a function named 'reverse_string' that takes a string slice ('&str') as input and returns a new 'String' containing the reverse of the input string.
Inside the function:

Create a new 'String' named 'reversed_string' to store the reversed string.
Iterate over the characters of the input string in reverse order using '.chars().rev()'.
For each character 'c', we append it to the 'reversed_string' using '.push(c)'.

Finally, we return the 'reversed_string' as the result of the function.
In the 'main' function, we define an input string.
We call the 'reverse_string' function with the input string and store the result in a variable named 'reversed'.
We then print both the original and reversed strings.

Rust Code Editor:

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