20 lines
417 B
Perl
20 lines
417 B
Perl
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#!/usr/bin/perl
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$number=<>; # read a number from the keyboard
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chomp $number; # remove linefeed
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$factorial=factorial($number);
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# The subroutine
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sub factorial {
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$input = shift; # read passed argument
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return 0 if $input==0;
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$result=1;
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foreach (1 .. $input) { # '..' generates a range
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$result *= $_;
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}
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return $result;
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}
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print "$number factorial is $factorial\n";
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