First Module Exercises

First challenge

Create a function that receives an enumerator as a parameter with the following options: .addition, .subtraction, .multiplication , .division and 2 numbers.

Print the operation according to the selected enumerator.

operation(.addition, firstNumber: 3, secondNumber: 4) 
// 7 

Second challenge

Create a function that receives an integer and prints whether the value is positive, negative or zero.

Print the result to the console.

comparison(number: -1)
// negative 

Third challenge

Create a function that receives an integer and prints that number multiplied from 1 to 10.

multiply(number: 5)
// 5x1 = 5
// 5x2 = 10
// 5x3 = 15
// 5x4 =20
// 5x5 = 25
// 5x6 = 30
// 5x7 = 35
// 5x8 = 40
// 5x9 = 45
// 5x10 = 50

Fourth challenge

Make a function that receives a string that simulates a password and returns true if they comply with the rules or false if they do not.

Rules:

• Min 6 characters
• Contains a capital letter
• Contain a number
• Contain a point

login(password: "pass")
// false

Fifth challenge

Make a function that receives an optional string and prints that same string without the optional value. If the value is nil print "empty value".

let testString: String? = "Hello world"
optionals(string: testString)
// “Hello world”

Sixth challenge

Given an optional string, print "It's empty! You ripped me off!" when it's nil, "Thanks for my cat Schrödinger!" if input is "🐈" and "This ain't a cat!" when none of the others.

receiveBox(with: "🐈")
// "Thanks for my cat Schrödinger!"
 
receiveBox(with: nil)
// "It's empty! You ripped me off!"

receiveBox(with: "lol")
// "This ain't a cat!"

Seventh challenge

Transform the snakes and ladders game code into a function that receives an array of numbers, which will represent dice rolls. Return and print the current position after iterating over all members of the array. Keep the same snakes/ladders values and positions.

let rolls = [2,3,5,6,5,4]
game(diceRolls: rolls)
// 24

Eigth challenge

Implement the Sieve of Eratosthenes algorithm in Swift from the provided unit tests. Return and print the resulting array containing only the prime numbers within the range.

• The only parameter is the max number.
• 0 and 1 are not prime numbers.
• The next available number is marked as prime but the next multiples up to the max number are not.
• Find the next prime number and repeat the previous step until reaching max number.

PrimeCalculator.calculate(upTo: 10)
// [2,3,5,7]

PrimeCalculator.calculate(upTo: 50)
// [2,3,5,7,11,13,17,19,23,29,31,37,41,43,47]

PrimeCalculator.calculate(upTo: 85)
// [2,3,5,7,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73,79,83]

Ninth challenge

Given an array of people, find the youngest, the oldest and the difference in age between them, and return their respective ages and the age difference.

struct Person {
    let name: String
    let age: Int
}

let son = Person(name: "Juan", age: 19)
let daughter = Person(name: "Maria", age: 12)
let mother = Person(name: "Benita", age: 60)
let father = Person(name: "Camilo", age: 58)

let family = [daughter, son, mother, daughter]

findAgeDifference(for: family)
// (oldest: 60, youngest: 12, ageDifference: 48)

Tenth challenge

Write a closure that takes an array of optional strings and returns a new string that is the concatenation of all the strings in the array. Remember to use the methods map, filter and reduce to find the solution.

let someStrings: [String?] = ["This", "is", nil, "not", nil, "a", "drill", nil, "!"]
// This is not a drill!