My Advent of Code solutions in Python.
kevinyap.ca/2019/12/going-fast-in-advent-of-code/
advent-of-code
python
Update 2017/day18.py
The two programs in Part 2 don't need to run in lockstep, so we only
actually need to yield at `rcv` instructions (each program can execute
independently until it gets stuck waiting to receive a value). This
means that no special logic needs to be introduced for Part 1.
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2017/day18.py
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2017/day18.py
···
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from collections import deque, defaultdict
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def duet_program(ops, regs, snd_q, rcv_q, part_1=False):
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def duet_program(instrs, snd_q, rcv_q, pid=None):
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regs = defaultdict(int)
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if pid is not None:
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regs['p'] = pid
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pc = 0
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sends = 0
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while 0 <= pc < len(ops):
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op, x, y = ops[pc]
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while 0 <= pc < len(instrs):
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op, x, y = instrs[pc]
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y = regs[y] if y.isalpha() else int(y)
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if op == 'snd':
···
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elif op == 'mod':
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regs[x] %= y
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elif op == 'rcv':
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if part_1:
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raise StopIteration
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if len(rcv_q) > 0:
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regs[x] = rcv_q.pop()
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else:
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if len(rcv_q) > 0:
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regs[x] = rcv_q.pop()
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else:
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yield op, sends
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continue
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yield op, sends
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continue
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elif op == 'jgz':
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if (regs[x] if x.isalpha() else int(x)) > 0:
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pc += y
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yield op, sends
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continue
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pc += 1
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yield op, sends
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raise StopIteration
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# Read puzzle input
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OPS = []
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INSTRS = []
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for line in fileinput.input():
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parts = line.strip().split()
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op, x = parts[:2]
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y = 'foo' if len(parts) == 2 else parts[2]
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OPS.append((op, x, y))
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instr = line.strip() + ' foo'
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op, x, y = instr.split()[:3]
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INSTRS.append((op, x, y))
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# Part 1
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regs = defaultdict(int)
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snd_queue = deque()
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for _ in duet_program(OPS, regs, snd_queue, deque(), part_1=True):
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pass
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program = duet_program(INSTRS, snd_queue, deque())
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next(program)
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print "Value of recovered frequency:", snd_queue[0]
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# Part 2
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regs_0 = defaultdict(int)
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regs_1 = defaultdict(int)
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regs_0['p'] = 0
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regs_1['p'] = 1
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queue_0 = deque()
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queue_1 = deque()
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program_0 = duet_program(INSTRS, queue_1, queue_0, pid=0)
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program_1 = duet_program(INSTRS, queue_0, queue_1, pid=1)
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last_op_0 = None
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last_op_1 = None
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program_0 = duet_program(OPS, regs_0, queue_1, queue_0)
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program_1 = duet_program(OPS, regs_1, queue_0, queue_1)
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while not (last_op_0 == last_op_1 == 'rcv' and len(queue_0) == len(queue_1) == 0):
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last_op_0, _ = next(program_0)