fn concatenate_strings(a: &String;, b: &String;) -> String {
    let mut output = String::new();
    output.push_str(a);
    output.push_str(b);
    output
}


fn main() {

    
    let string1 = String::from("HI,");
    let string2 = String::from(" there");


    let concatenated_string = concatenate_strings(&string1;, &string2;);
    println!("{} ", concatenated_string);
}