Advent of Code 2018

day1.swift

// Part one

let input = """
"""

print(input.split(separator: "\n").map {
  Int($0)!
}.reduce(0, +))

// Part Two

let input = """
"""

// Frequencies we reach
let values = input.split(separator: "\n").map {
  Int($0)!
}

var freqs = [Int]()
var currentFreq = 0
var check = true

while check {
  for value in values {
    if !freqs.contains(currentFreq) {
      freqs.append(currentFreq)
    } else {
      check = false
      break
    }
    
    currentFreq += value
  }
}

print(currentFreq)

day2.swift

// Part one

let input = """
"""

let boxes = input.split(separator: "\n")

var twoLetters = 0
var threeLetters = 0

var checkedLetters = [Character]()
var twoDone = false
var threeDone = false

for box in boxes {
  for char in box {
    guard !checkedLetters.contains(char) else {
      continue
    }
    
    checkedLetters.append(char)
    
    let charsInBox = box.filter { $0 == char }.count
    if !twoDone && charsInBox == 2 {
      twoDone = true
      twoLetters += 1
    }
    
    if !threeDone && charsInBox == 3 {
      threeDone = true
      threeLetters += 1
    }
    
    if twoDone && threeDone {
      break
    }
  }
  
  checkedLetters.removeAll()
  twoDone = false
  threeDone = false
}

print(twoLetters * threeLetters)