19 lines
381 B
Text
19 lines
381 B
Text
procedure power_set (s)
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if *s = 0
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then suspend set ()
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else {
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head := set(?s)
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every ps := power_set (s -- head) do {
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suspend ps
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suspend ps ++ head
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}
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}
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end
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procedure main ()
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every s := power_set (set(1,2,3,4)) do { # power_set's values are generated by 'every'
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writes ("[ ")
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every writes (!s || " ")
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write ("]")
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}
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end
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