pizza_party.rs

// Pizza Party (#8 from https://pragprog.com/book/bhwb/exercises-for-programmers)

// Write a program to evenly divide pizzas. Prompt for the number of people, the
// number of pizzas, and the number of slices per pizza. Ensure that the number of
// pieces comes out even. Display the number of pieces of pizza each person should
// get. If there are leftovers, show the number of leftover pieces.

// Challenges
// * Revise the program to ensure that inputs are entered as numeric values.
// * Alter the output so it handles pluralization properly, for example:
//     * Each person gets 2 pieces of pizza. or
//     * Each person gets 1 piece of pizza.
// * Handle the output for leftover pieces appropriately as well.
// * Create a variant of the program that:
//     * prompts for the number of people and the number of pieces each person wants
//     * and calculate how many full pizzas you need to purchase.

use std::env;

fn main() {
    let args: Vec<String> = env::args().collect();
    let people: u32 = parse_cli_arg((&args[1]).to_string());
    let pizzas: u32 = parse_cli_arg((&args[2]).to_string());
    let pizza_slices: u32 = parse_cli_arg((&args[3]).to_string());

    let total_slices: u32 = pizza_slices * pizzas;
    let slices_per_person: u32 = total_slices / people;
    let slices_leftover: u32 = total_slices % people;

    println!("{} people with {} pizzas.", people, pizzas);
    println!("Each person gets {} pieces of pizza.", slices_per_person);
    println!("There are {} leftover pieces.", slices_leftover);
}

fn parse_cli_arg(arg: String) -> u32 {
    match arg.trim().parse() {
        Ok(num) => num,
        Err(_) => 0,
    }
}