Slice and change string

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examples/strings/slice-and-change/src/main.rs

fn main() {
    let mut text = String::from("Foobar");
    println!("{}", text);

    let slice = &text[0..=2];
    println!("{}", slice);

    text.clear();
    text.push_str("qwerty");
    println!("{}", text);
    //println!("{}", slice);
}