38 lines
919 B
Plaintext
38 lines
919 B
Plaintext
func EncodeNegBase(Num n, Num b { .~~ (-36 .. -2) }) {
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var out = []
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var r = 0
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while (n) {
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(n, r) = divmod(n, b)
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if (r < 0) {
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n += 1
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r -= b
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}
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out << r.base(-b)
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}
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return (out.join.flip || "0")
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}
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func DecodeNegBase(Str s, Num b { .~~ (-36 .. -2) }) {
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var total = 0
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for i,c in (s.flip.chars.kv) {
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total += (Num(c, -b) * b**i)
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}
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return total
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}
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say (" 10 in base -2: ", EncodeNegBase(10, -2))
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say ("146 in base -3: ", EncodeNegBase(146, -3))
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say (" 15 in base -10: ", EncodeNegBase(15, -10))
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say '-'*25
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say ("11110 from base -2: ", DecodeNegBase("11110", -2))
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say ("21102 from base -3: ", DecodeNegBase("21102", -3))
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say (" 195 from base -10: ", DecodeNegBase("195", -10))
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say '-'*25
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# Extra
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say ("25334424 in base -31: ", EncodeNegBase(25334424, -31))
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say ("sidef from base -31: ", DecodeNegBase("sidef", -31))
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