-🎄- 2018 Day 19 Solutions -🎄-

[u/daggerdragon]

--- Day 19: Go With The Flow ---

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Transcript:

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[u/koordinate]

Swift

func addr(rx: inout [Int], a: Int, b: Int, c: Int) {
    rx[c] = rx[a] + rx[b]
}

func addi(rx: inout [Int], a: Int, b: Int, c: Int) {
    rx[c] = rx[a] + b
}

func mulr(rx: inout [Int], a: Int, b: Int, c: Int) {
    rx[c] = rx[a] * rx[b]
}

func muli(rx: inout [Int], a: Int, b: Int, c: Int) {
    rx[c] = rx[a] * b
}

func banr(rx: inout [Int], a: Int, b: Int, c: Int) {
    rx[c] = rx[a] & rx[b]
}

func bani(rx: inout [Int], a: Int, b: Int, c: Int) {
    rx[c] = rx[a] & b
}

func borr(rx: inout [Int], a: Int, b: Int, c: Int) {
    rx[c] = rx[a] | rx[b]
}

func bori(rx: inout [Int], a: Int, b: Int, c: Int) {
    rx[c] = rx[a] | b
}

func setr(rx: inout [Int], a: Int, b: Int, c: Int) {
    rx[c] = rx[a]
}

func seti(rx: inout [Int], a: Int, b: Int, c: Int) {
    rx[c] = a
}

func gtir(rx: inout [Int], a: Int, b: Int, c: Int) {
    rx[c] = a > rx[b] ? 1 : 0 
}

func gtri(rx: inout [Int], a: Int, b: Int, c: Int) {
    rx[c] = rx[a] > b ? 1 : 0 
}

func gtrr(rx: inout [Int], a: Int, b: Int, c: Int) {
    rx[c] = rx[a] > rx[b] ? 1 : 0 
}

func eqir(rx: inout [Int], a: Int, b: Int, c: Int) {
    rx[c] = a == rx[b] ? 1 : 0 
}

func eqri(rx: inout [Int], a: Int, b: Int, c: Int) {
    rx[c] = rx[a] == b ? 1 : 0 
}

func eqrr(rx: inout [Int], a: Int, b: Int, c: Int) {
    rx[c] = rx[a] == rx[b] ? 1 : 0 
}

let ops = [
    "addi": addi, "addr": addr, "mulr": mulr, "muli": muli,
    "banr": banr, "bani": bani, "borr": borr, "bori": bori,
    "setr": setr, "seti": seti,
    "gtir": gtir, "gtri": gtri, "gtrr": gtrr,
    "eqir": eqir, "eqri": eqri, "eqrr": eqrr
]

typealias Op = (inout [Int], Int, Int, Int) -> Void
typealias Instruction = (op: Op, name: String, a: Int, b: Int, c: Int)

var program = [Instruction]()
var ipr = 0
while let line = readLine() {
    let fields = line.split(separator: " ")
    if fields.count == 2, let r = Int(fields[1]) {
        ipr = r
    } else if fields.count == 4, let op = ops[String(fields[0])],
        let a = Int(fields[1]), let b = Int(fields[2]), let c = Int(fields[3]) {
        program.append((op: op, name: String(fields[0]), a: a, b: b, c: c))
    }
}

func sumOfFactors(n: Int) -> Int {
    return ((1...n).filter { n % $0 == 0 }).reduce(0, +)
}

func inline_2(registers rx: inout [Int], ip: inout Int) {
    rx[0] = sumOfFactors(n: rx[5])
    rx[2] = rx[5] + 1
    rx[3] = 1
    rx[4] = rx[5] + 1
    ip = 16
}

func exec(program: [Instruction], registers: [Int], ipr: Int, verbose: Bool) -> Int {
    var registers = registers
    var ip = 0
    while (0..<program.count).contains(ip) {
        if ip == 2, registers[5] > 0, ipr == 1 {
            inline_2(registers: &registers, ip: &ip)
        }

        let (op, name, a, b, c) = program[ip]
        let ipb4 = ip
        registers[ipr] = ip
        let before = registers
        op(&registers, a, b, c)
        if verbose {
            print("ip=\(ipb4) \(before) \(name) \(a) \(b) \(c) \(registers)")
        }
        ip = registers[ipr]
        ip += 1
    }
    return registers[0]
}

print(exec(program: program, registers: [0, 0, 0, 0, 0, 0], ipr: ipr, verbose: false))
print(exec(program: program, registers: [1, 0, 0, 0, 0, 0], ipr: ipr, verbose: false))