Problem Solving Preparation

Let's look at some helpful methods that will help you in solving coding problems on strings.

Convert String to &str

    let string = String::from("Hello World");
    let slice = string.as_str();

Convert &str to String

    let slice = "Hello World";
    let string = slice.to_string();

Create a String with given values

#![allow(unused)]
fn main() {
    let name = "Hashirama";
    let dialogue = format!("I've been waiting for you, {}!", name);
    println!("{dialogue}");
}

Replace a slice or a character in a string

#![allow(unused)]
fn main() {
    let mut sentence = "mife is movemy";
    let new_sentence =  sentence.replace("m", "l");
    println!("{new_sentence}");
}

Convert a &str into Vec

If you want to access individual values in a string slice, it is better to convert it into a vector of chars

    let my_str: &str = "123456789";
    let char_vec: Vec<char> = my_str.chars().collect();

The chars method returns an iterator over the individual characters of the slice and the collect method takes the characters and turn them into a collection.

Access nth character in a string

The nth() is used to return the nth element of the iterator. This means nth must be used with an iterator or in case of a string, chars().

#![allow(unused)]
fn main() {
    let my_str: &str = "Secret no: 4";
    let num = my_str.chars().nth(11).unwrap();
    println!("{num}");
}

Split a string

The split¹ method in Rust is used to divide a string slice into an iterator of substrings based on a specified delimiter.

#![allow(unused)]
fn main() {
    let v: Vec<&str> = "Mary had a little lamb".split(' ').collect();
    assert_eq!(v, ["Mary", "had", "a", "little", "lamb"]);
}