Challenge 2: println! With Placeholders — Possible Solution
====================================================================

fn main() {
    let year = 2026;
    println!("Year: {}", year);

    let language = "Rust";
    println!("Language: {}", language);
}

WHY THIS WORKS AS AN ANSWER
------------------------------
{} is println!'s placeholder syntax — it's substituted with whatever
value is passed as the next argument after the format string, the
same underlying idea as Go's %d/%s verbs in Printf, just using one
generic placeholder rather than type-specific ones (Rust infers how to
display the value automatically for common types like integers and
strings).

Two SEPARATE println! calls are used, one per required line, rather
than combining both into a single call or building the output via
string concatenation (e.g. "Year: " + year.to_string()) — using the
placeholder form directly is both simpler and the idiomatic Rust way
to interpolate a value into printed output, avoiding manual
string-building entirely.