// 👇 The lines below, starting with `///`, are called **documentation comments**.
//    They attach documentation to the item that follows them. In this case, the `speed` function.
//    If you run `cargo doc --open` from this exercise's directory, Rust will generate
//    HTML documentation from these comments and open it in your browser.

/// Given the start and end points of a journey, and the time it took to complete it,
/// calculate the average speed.
pub fn speed(start: u32, end: u32, time_elapsed: u32) -> u32 {
    // TODO: define a variable named `distance` with the right value to get tests to pass
    //  Do you need to annotate the type of `distance`? Why or why not?
    let distance = end - start;
    // Don't change the line below
    distance / time_elapsed
}

#[cfg(test)]
mod tests {
    use crate::speed;

    #[test]
    fn case1() {
        assert_eq!(speed(0, 10, 10), 1);
    }

    #[test]
    fn case2() {
        assert_eq!(speed(10, 30, 10), 2);
    }

    #[test]
    fn case3() {
        assert_eq!(speed(10, 31, 10), 2);
    }
}