rust-book/ownership/src/main.rs


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fn main() {
    //let words = String::from("hello there world");
    //let words = "hello there world";
    //let first = first_word(&words);
    //let second = second_word(&words);
    //let last = last_word(&words);
    //println!("{}\n{}", first, last);
    let a = [1, 2, 3, 4, 5];
    let slice = &a[1..4];

    for each in slice {
        println!("{}", each);
    }
}

fn first_word(s: &str) -> &str {
    let bytes = s.as_bytes();

    for (i, &item) in bytes.iter().enumerate() {
        if item == b' ' {
            return &s[..i];
        }
    }

    &s
}

fn second_word(s: &str) -> &str {
    let bytes = s.as_bytes();

    for (i, &item) in bytes.iter().enumerate() {
        if item == b' ' {
            return &s[i + 1..];
        }
    }

    &s
}

fn last_word(s: &str) -> &str {
    let bytes = s.as_bytes();
    let mut result = "";

    for (i, &item) in bytes.iter().enumerate() {
        if item == b' ' {
            result = &s[i + 1..];
        }
    }

    &result
}