56 lines
1.2 KiB
Python
Executable File
56 lines
1.2 KiB
Python
Executable File
#!/usr/bin/python3
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from pprint import pprint
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prog = []
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with open("input") as fh:
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for ln in fh:
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op, arg = ln.split()
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prog.append((op, int(arg)))
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class InfiniteLoopError(Exception):
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pass
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def run(prog):
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acc = 0
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ip = 0
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seen = set()
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while True:
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if ip == len(prog):
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return acc
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if ip in seen:
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raise InfiniteLoopError(acc)
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seen.add(ip)
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op = prog[ip][0]
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arg = prog[ip][1]
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if op == "acc":
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acc += arg
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ip += 1
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elif op == "jmp":
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ip += arg
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elif op == "nop":
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ip += 1
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def fixprog(prog):
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try:
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# first try original:
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acc = run(prog)
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print(acc)
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except InfiniteLoopError:
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print("infinite loop")
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for i in range(len(prog)):
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op = prog[i][0]
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if op not in ("jmp", "nop"):
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continue
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newop = "nop" if op == "jmp" else "jmp"
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fixedprog = list(prog)
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fixedprog[i] = (newop, prog[i][1])
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print("fixed", i, fixedprog[i])
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try:
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acc = run(fixedprog)
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print(acc)
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except InfiniteLoopError:
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print("infinite loop")
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fixprog(prog)
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