Arrays in Rust

1. Arrays in Rust
2. Rust array of numbers, length of array
3. Array of strings - access element by index
4. Array of structs
5. Array iterate on elements
6. Rust array iterate over idices
7. Rust array iterate indices and elements with enumerate
8. Rust arrays are not mutable
9. Make the Rust array mutable
10. Creating an array with the same value
11. Exercise: Count digits
12. Solution: Count digits