# Input: Register A: <#>
#        Register B: <#>
#        Register C: <#>
#        <blank line>
#        Program: <#>,<#>,... (all 0 to 7)
# Output: instruction pointer starts ta start (0), default +2,
#           if goes past end then halts
#         <combo operand>: 0-3 = that value, 4-6 = A-C, 7 = unused
#         0 <combo operand> -> A = int(A / 2^CO)
#         1 <literal operand> -> B = xor(B, LO)
#         2 <CO> -> B = CO % 8
#         3 <LO> -> if A != 0 then jump to <LO>
#         4 <ignored> -> B = xor(B, C)
#         5 <CO> -> output CO % 8
#           multiple outputs separated by commas
#         6 <CO> -> B = int(A / 2^CO)
#         7 <CO> -> C = int(C / 2^CO)

def combo_value():
  if program[pointer + 1] <= 3:
    return program[pointer + 1]
  if program[pointer + 1] == 4:
    return a
  if program[pointer + 1] == 5:
    return b
  if program[pointer + 1] == 6:
    return c
  print ("pointer =", pointer)
  print ("program[pointer + 1] =", program[pointer + 1])
  raise Exception("Invalid combo operand")

a, b, c = -1, -1, -1
pointer = 0

line_count = 0
file = open("17_input.txt", "r")
for line in file:
  line = line.replace("\n", "")
  line_count += 1
  if line_count == 1:
    a = int(line.replace("Register A: ", ""))
  if line_count == 2:
    b = int(line.replace("Register B: ", ""))
  if line_count == 3:
    c = int(line.replace("Register C: ", ""))
  if line_count == 5:
    program = list(map(int, line.replace("Program: ", "").split(",")))

output = ""
while pointer >= 0 and pointer < len(program):
  if program[pointer] == 0:
    a = int(a / (2 ** combo_value()))
    pointer += 2
    continue
  if program[pointer] == 1:
    b = b ^ program[pointer + 1]
    pointer += 2
    continue
  if program[pointer] == 2:
    b = combo_value() % 8
    pointer += 2
    continue
  if program[pointer] == 3:
    if a == 0:
      pointer += 2
    else:
      pointer = program[pointer + 1]
    continue
  if program[pointer] == 4:
    b = b ^ c
    pointer += 2
    continue
  if program[pointer] == 5:
    output += "," + str(combo_value() % 8)
    pointer += 2
    continue
  if program[pointer] == 6:
    b = int(a / (2 ** combo_value()))
    pointer += 2
    continue
  if program[pointer] == 7:
    c = int(a / (2 ** combo_value()))
    pointer += 2
    continue
  print ("pointer =", pointer)
  print ("program[pointer] =", program[pointer])
  raise Exception("Invalid instruction")

print (output[1:])