Rust Taskbook Level 9.1

Задание 1

Given an integer:

rustlet num: u16 = 12345;

Find the smallest and largest digits in this number.

Задание 2

Given some URL:

rustlet url: &str = "http://test.com/dir1/dir2/dir3/page.html";

Get the domain name from it:

rust"test.com"

Задание 3

Given an array:

rust[
  [2, 4, 5],
  [1, 2, 3],
  [0, 1, 1],
  [5, 7, 1],
}

Sort the array elements in ascending order of the sum of the subarray elements.