iOS repl.it - Arrays Challenge Solution

arrays.swift

let numbers = [45, 73, 195, 53]

//Create a new array called computedNumbers
var computedNumbers = [
  numbers[0] * numbers[1], 
  numbers[1] * numbers[2], 
  numbers[2] * numbers[3], 
  numbers[3] * numbers[0]
]


print(computedNumbers)

func exercise() {

let numbers = [45, 73, 195, 53]

let computedNumbers = [
   numbers[0] * numbers[1], 
   numbers[1] * numbers[2], 
   numbers[2] * numbers[3], 
   numbers[3] * numbers[0]
]

print(computedNumbers)

}

func exercise() {

let numbers = [45, 73, 195, 53]

let a = numbers[0]*numbers[1]
let b = numbers[1]*numbers[2]
let c = numbers[2]*numbers[3]
let d = numbers[3]*numbers[0]
//Write your code here
let computedNumbers = [a,b,c,d] //Replace this comment with your code.

print(computedNumbers)

}

My solution is

var number = [45, 73, 195, 53]

var computedNumbers = [number[0] * number[1],
number[1] * number[2],
number[2] * number[3],
number[3] * number[0]
]

print(computedNumbers)

My solutions is:

let numbers = [45, 73, 195, 53]

let a = numbers [0]
let b = numbers [1]
let c = numbers [2]
let d = numbers [3]

let computedNumbers = [(ab),(bc),(cd),(da)]

print(computedNumbers)

Or this solution:

let numbers = [45, 73, 195, 53]

let computedNumbers = [numbers [0] * numbers [1],numbers [1] * numbers [2],numbers [2] * numbers [3], numbers [3] * numbers [0]]

print(computedNumbers)

Answer: [3285,14235,10335,2385]

func exercise() {

let numbers = [45, 73, 195, 53]

//Write your code here
var num = 0
var computedNumbers = [Int]()
while(num < numbers.count)
{
    computedNumbers.append(numbers[num]*numbers[(num+1)%numbers.count])
    num = num + 1
}
print(computedNumbers)

}

exercise()

func exercise() {

let numbers = [45, 73, 195, 53]

//Write your code here
var computedNumbers = [Int]()
 for i in 0..<numbers.count-1{
    computedNumbers.append(numbers[i]*numbers[(i+1)%numbers.count])
}
computedNumbers.append(numbers[0]*numbers[numbers.count-1])
print(computedNumbers)

}
exercise()

var numbers = [45, 73, 195, 53]
var computedNumbers = [numbers[0]*numbers[1], numbers[1]*numbers[2], numbers[2]*numbers[3], numbers[3]*numbers[0]]
print(computedNumbers)

ok got it.

var computedNumbers = [numbers[0]*numbers[1],numbers[1]*numbers[2],numbers[2]*numbers[3]]
print(computedNumbers)

var numbers = [45, 73, 195, 53] [0]

let computedNumbers = [45 * 73,73 * 195,195 * 53,53 * 45]

print(computedNumbers)

let numbers = [45, 73, 195, 53]

var numbersCopy = numbers
let firstNumber = numbersCopy.remove(at: 0)
numbersCopy.append(firstNumber)
let computedNumbers = zip(numbers, numbersCopy).map(*)

print(computedNumbers)

When I copy and paste my code from Xcode, the "*" are not showing between a+b etc... in this forum.
Does anyone know why?
It works perfectly in Xcode.

---

let numbers = [69, 73, 169, 173]

var a = numbers [0]
var b = numbers [1]
var c = numbers [2]
var d = numbers [3]

var computedNumbers = [ab, bc, cd, da]

print(computedNumbers)

let numbers = [45, 73, 195, 53]

let computedNumbers = numbers.enumerated().map { (index, element) -> Int in
    return element * numbers[(index+1) % numbers.count]
}


print(computedNumbers)

var numbers = [5, 3 1, 2, 4]

var computedNumbers: [Int] = ()

for index in 0..<numbers.count{
computedNumbers.append(numbers[index]*numbers[(index+1)%numbers.count])
}
print(computedNumbers)

var myArray = [45, 73, 195, 53]
var shiftedArray = myArray.dropFirst()
let computedArray = zip(myArray, shiftedArray).map { (a, b) in a * b }

func exercise() {

let numbers = [45, 73, 195, 53]

let computedNumbers = [numbers[0]*numbers[1], numbers[1]*numbers[2], numbers[2]*numbers[3], numbers[3]*numbers[0]]



print(computedNumbers)

}

I am sure there is a much short and efficient code available to do this, but then I am just a beginner and it worked for me..:)

//The solution can vary depending on the requirement, I come up with two

//Solution 1

var numbers = [45, 73, 195, 53]

var computedNumbers = [ numbers[0] * numbers[1], numbers[1] * numbers[2], numbers[2] * numbers[3], numbers[3] * numbers[0] ]

print(computedNumbers)

//Solution 2

var newNumbers = [45, 73, 195, 53]

var a = newNumbers[0] var b = newNumbers[1] var c = newNumbers[2] var d = newNumbers[3]

var newComputedNumbers = [ a_b, b_c, c_d, d_a ]

print(newComputedNumbers)

//Output from both [3285, 14235, 10335, 2385] [3285, 14235, 10335, 2385]

This would be considered incorrect since you haven't put "*" between the variables.

let numbers = [45, 73, 195, 53]

//Write your code here
var computedNumbers: [Int] = []
for (index, value) in numbers.enumerated() {
    computedNumbers.append(numbers [ (index+1) % numbers.count ] * value)
}
print(computedNumbers)

let numbers = [45, 73, 195, 53]
var computednumbers = [numbers[0] * numbers[1], numbers[1] * numbers[2], numbers[2] * numbers[3], numbers[3] * numbers[0]]
print(computedNumbers)

let numbers = [45, 73, 195, 53]

var computedNumbers = [
numbers[0]*numbers[1],
numbers[1]*numbers[2],
numbers[2]*numbers[3],
numbers[3]*numbers[0]
]

print(computedNumbers)

func exercise() {

    let numbers = [45, 73, 195, 53]
    
    //Write your code here
    let computedNumbers = numbers
        .enumerated()
        .map({
            index, number in
            number * numbers[(index + 1) % numbers.count]
        })
    print(computedNumbers)
}

I actually used Var and it worked. I guess it was a bit longer though

func exercise() {

let numbers = [45, 73, 195, 53]

var numbers1 = numbers [0]
var numbers2 = numbers [1]
var numbers3 = numbers [2]
var numbers4 = numbers [3]

let computedNumbers = [numbers1*numbers2, numbers2*numbers3, numbers3*numbers4, numbers4*numbers1]


print(computedNumbers)

}

func exercise() {

let numbers = [45, 73, 195, 53]

let item1 = numbers[0] * numbers[1]
let item2 = numbers[1] * numbers[2]
let item3 = numbers[2] * numbers[3]
let item4 = numbers[3] * numbers[0]

let computedNumbers = [item1, item2, item3, item4]

print(computedNumbers)

}

exercise()

var numbers = [45, 73, 195, 53]
var computedArray: [Int] = []

for num in 0..<numbers.count {
let nextIndex = (num + 1) % numbers.count
let multipliedNum = numbers[num] * numbers[nextIndex]
computedArray.append(multipliedNum)
}

print(computedArray)

let numbers = [45, 73, 195, 53]
    
//Write your code here
let computedNumbers = [
    numbers[0] * numbers[1],
    numbers[1] * numbers[2],
    numbers[2] * numbers[3],
    numbers[3] * numbers[0],
]

var numeros: [Int] = [ 3, 7, 10, 24]

var computadNumber: [Int] = [numeros[0]*numeros[1], numeros[1]*numeros[2], numeros[2]*numeros[3], numeros[3]*numeros[0]]

print(computadNumber)

func exercise() {

let numbers = [45, 73, 195, 53]

let computedNumbers = [numbers[0] * numbers[1], numbers[1] * numbers[2], numbers[2] * numbers[3], numbers[3] * numbers[0]]


print(computedNumbers)

}

var lst = [1,2,3,4,5]

var lst2 = Int

for i in 0...lst.count-2{
let x = lst[i] * lst[i+1]
lst2.append(x)
}
let y = lst[lst.count-1] * lst[0]
lst2.append(y)
print(lst2)

let numbers = [45, 73, 195, 53];

var computedNumbers = [Int]();

for i in 0 ..< (numbers.count) {
    if (i < numbers.count - 1) {
        computedNumbers.append(numbers[i] * numbers[i + 1])
    }
    else {
        computedNumbers.append(numbers[i] * numbers[0])
    }
}

print(computedNumbers);