fn main() {
    let s = String::from("0123456789");
    let s2 = &s[..];
    let s3 = &s[2..5];
    let s4 = &s[..5];
    let s5 = &s[2..];
    let s6 = &s[2..=5];
    println!("s: {}", s);
    println!("s2: {}", s2);
    println!("s3: {}", s3);
    println!("s4: {}", s4);
    println!("s5: {}", s5);
    println!("s6: {}", s6);

    /*
    s: 0123456789
    s2: 0123456789
    s3: 234
    s4: 01234
    s5: 23456789
    s6: 2345
        */
}