Day 1 - variables, constants, strings, and numbers
Day 2 - Booleans, string interpolation, and checkpoint 1
Day 3– Arrays, dictionaries, sets, and enums
Day 4 – type annotations and checkpoint 2
Day 5 – if, switch, and the ternary operator
Day 6 – loops, summary, and checkpoint 3
Day 7 – functions, parameters, and return values
Day 8 – default values, throwing functions, and checkpoint 4
Day 9 – closures, passing functions into functions, and checkpoint 5
Day 10 – structs, computed properties, and property observers
Day 11 – access control, static properties and methods, and checkpoint 6
Day 12 – classes, inheritance, and checkpoint 7
Day 13 – protocols, extensions, and checkpoint 8
Day 14 – optionals, nil coalescing, and checkpoint 9
Day 15 – Swift review
Checkpoint 1: Solution
Checkpoint 2: Solution
Checkpoint 3: Solution
Checkpoint 4: Solution
Checkpoint 5: Solution
Checkpoint 6: Solution
Checkpoint 7: Solution
Checkpoint 8: Solution
Checkpoint 9: Solution