RosettaCodeData/Task/Fibonacci-sequence/Tailspin/fibonacci-sequence-3.tailspin
2023-07-01 13:44:08 -04:00

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Text

templates nthFibonacci
@: {n0: 0"1", n1: 1"1"};
def sign: $ -> \(<0..> 1! <> -1!\);
1..$*$sign -> $sign -> #
$@.n0!
<=1>
@: {n0: $@.n1, n1: $@.n0 + $@.n1};
<=-1>
@: {n0: $@.n1 - $@.n0, n1: $@.n0};
end nthFibonacci