41 lines
875 B
Ruby
41 lines
875 B
Ruby
# frozen_string_literal: true
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def run(mem)
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pc = 0
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loop do
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case mem[pc]
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when 1
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r1, r2, r3 = mem[pc+1], mem[pc+2], mem[pc+3]
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mem[r3] = mem[r1] + mem[r2]
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pc += 4
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when 2
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r1, r2, r3 = mem[pc+1], mem[pc+2], mem[pc+3]
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mem[r3] = mem[r1] * mem[r2]
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pc += 4
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when 99
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return mem[0]
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else
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raise StandardError, "unexpected opcode: #{opcode}"
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end
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end
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end
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def solve(program)
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(0...99).each do |noun|
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(0...99).each do |verb|
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puts "Trying noun = #{noun}, verb = #{verb} ..."
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mem = program.clone
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mem[1] = noun
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mem[2] = verb
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output = run(mem)
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puts "Output: #{output}"
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if output == 19690720
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return [noun, verb, 100*noun + verb]
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end
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end
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end
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end
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input = File.read(File.join(__dir__, 'input'))
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program = input.split(',').map(&:to_i)
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puts solve(program)
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