مولّد مخطط استدعاءات Rust

fn run() -> i32 {
    let total = sum_invoices(fetch_invoices());
    report(total);
    total
}

fn fetch_invoices() -> Vec<i32> {
    vec![1000, 2500, 400]
}

fn sum_invoices(amounts: Vec<i32>) -> i32 {
    amounts.iter().sum()
}

fn report(total: i32) {
    println!("total: {total}");
}