22 lines
354 B
Plaintext
22 lines
354 B
Plaintext
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###
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### fib-cached
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###
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## Chapter 3 section 2
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# Compute the number of pairs of rabbits alive in month n
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{ my %cache;
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sub fib {
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my ($month) = @_;
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unless (exists $cache{$month}) {
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if ($month < 2) { $cache{$month} = 1 }
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else {
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$cache{$month} = fib($month-1) + fib($month-2);
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}
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}
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return $cache{$month};
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}
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}
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