Evaluate binomial coefficients: Difference between revisions
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<pre>10</pre>
A useful optimization would use a symmetry property of the binomial coefficient:
<lang perl6>sub infix:<choose> { [*] ($^n ... 0) Z/ 1 .. min($n - $^p, $p) }</lang>
One drawback of this method is that it returns a Rat, not an Int. If we really worry about it, we can enforce the conversion:
<lang perl6>sub infix:<choose> { ([*] ($^n ... 0) Z/ 1 .. min($n - $^p, $p)).Int }</lang>
=={{header|PL/I}}==
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