mirror of
https://github.com/badvision/lawless-legends.git
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63 lines
1.1 KiB
Ruby
Executable File
63 lines
1.1 KiB
Ruby
Executable File
#!/usr/bin/env ruby
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MULT = 32
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#BIG_NUM = 65521 # should be prime
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#BIG_NUM = 65519
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BIG_NUM = 32749
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def linCong(seed)
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if seed == 0
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seed = 1
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else
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seed &= 0x7FFF
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seed >= BIG_NUM and seed -= BIG_NUM
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5.times {
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seed <<= 1
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seed >= BIG_NUM and seed -= BIG_NUM
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}
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end
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return seed
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end
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def rnd02(seed)
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magic = 0x2227
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if seed == 0
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seed = magic
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elsif seed == 0x8000
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seed = 0
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else
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seed <<= 1
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if (seed & 0x8000) > 0
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seed = (seed & 0x7fff) ^ magic
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end
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end
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return seed
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end
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done = {}
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minLoop = nil
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(BIG_NUM..0xFFFF).each { |invalSeed|
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out = linCong(invalSeed)
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out >= 0 && out < BIG_NUM or raise("Bad: $%x -> $%x" % [invalSeed, out])
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}
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(0..BIG_NUM-1).each { |startSeed|
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next if done[startSeed]
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n = 0
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seed = startSeed
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loop do
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print "%016b %04X -> " % [seed, seed]
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seed = linCong(seed)
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puts "%04X" % seed
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if done[seed]
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length = n - done[seed]
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puts "loop at #{startSeed} -> #{seed}: length=#{length}"
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minLoop = minLoop ? [minLoop, length].min : length
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break
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end
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done[seed] = n
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n += 1
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end
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}
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puts "minLoop=#{minLoop}"
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