17 lines
378 B
Plaintext
17 lines
378 B
Plaintext
open Num
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let mul (a,b,c) (d,e,f) = let bxe = b*/e in
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(a*/d +/ bxe, a*/e +/ b*/f, bxe +/ c*/f)
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let id = (Int 1, Int 0, Int 1)
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let rec pow a n =
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if n=0 then id else
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let b = pow a (n/2) in
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if (n mod 2) = 0 then mul b b else mul a (mul b b)
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let fib n =
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let (_,y,_) = (pow (Int 1, Int 1, Int 0) n) in
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string_of_num y
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;;
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Printf.printf "fib %d = %s\n" 300 (fib 300)
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