19 lines
418 B
Forth
19 lines
418 B
Forth
# Least Common Multiple
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The least common multiple of two integers a and b, is the
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smallest positive integer that is divisible by both a and b.
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This implements a word to find this in RETRO.
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It uses a formula that reduces the problem to computing the
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greatest common divisor (gcd), as in:
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lcm(a,b) = |a*b| / gcd(a,b)
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~~~
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:gcd (ab-n)
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[ tuck mod dup ] while drop ;
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:lcm (ab-n)
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dup-pair gcd [ * ] dip / ;
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~~~
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