85 lines
1.3 KiB
Crystal
85 lines
1.3 KiB
Crystal
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require "advent"
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INPUT = input(2020, 8).lines
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def part1
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acc = 0
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pc = 0
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visited = Set(Int32).new
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input = INPUT.clone.map do |s|
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code, int = s.split(" ")
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{code, int.to_i32}
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end
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loop do
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if visited.includes? pc
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break
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end
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visited << pc
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code, int = input[pc]
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case input[pc][0]
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when "acc"
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acc += int
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pc += 1
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when "jmp"
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pc += int
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when "nop"
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pc += 1
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end
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end
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end
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def run(prog)
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acc = 0
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pc = 0
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visited = Set(Int32).new
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loop do
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if visited.includes? pc
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return false
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end
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return acc if pc >= prog.size
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visited << pc
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code, int = prog[pc]
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case prog[pc][0]
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when "acc"
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acc += int
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pc += 1
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when "jmp"
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pc += int
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when "nop"
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pc += 1
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end
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end
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end
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def part2
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input = INPUT.clone.map do |s|
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code, int = s.split(" ")
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{code, int.to_i32}
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end
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jnp = [] of Int32
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input.each_with_index do |e, i|
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op, int = e
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jnp << i if op == "jmp" || op == "nop"
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end
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jnp.each do |i|
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prog = input.clone
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if prog[i][0] == "jmp"
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prog[i] = {"nop", prog[i][1]}
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else
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prog[i] = {"jmp", prog[i][1]}
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end
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case i = run(prog)
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when Bool
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next
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when Int32
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return i
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end
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end
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end
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puts part1
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puts part2
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