Re^2: John Guttag's book - 2nd exercise. My attempt in Perl.

Should while (my $current = shift) be while ( defined( my $current = shift ) ) ? Otherwise it seems to fail if @array contains 0.

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Re^3: John Guttag's book - 2nd exercise. My attempt in Perl. by Laurent_R (Canon) on May 22, 2017 at 19:19 UTC
Yes, Anonymous Monk, you're correct, this `while` loop has a bug when one of the values in the array is 0. IMHO, this array traversal should really be made with a `for` loop, as it is usually better to use a `for` loop to iterate over an array, but the OP did not specify very clearly what was authorized and what not. This is what it might look like with a `for` loop. `use strict; use warnings; my @array = (-11,-13,4, 22, 17); print find_max_odd(@array), "\n"; sub find_max_odd { my $max; for my $num (@_) { next unless $num % 2; $max = $num unless defined $max; $max = $num if $num > $max; } return defined $max ? $max : "No odd number found\n"; # this co +uld be replaced with if conditional statements if needed }` [download]	[reply] [d/l] [select]

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Re^3: John Guttag's book - 2nd exercise. My attempt in Perl.
by Laurent_R (Canon) on May 22, 2017 at 19:19 UTC

Anonymous Monk

while

IMHO, this array traversal should really be made with a for loop, as it is usually better to use a for loop to iterate over an array, but the OP did not specify very clearly what was authorized and what not.

This is what it might look like with a for loop.

use strict;
use warnings;

my @array = (-11,-13,4, 22, 17);
print find_max_odd(@array), "\n";
sub find_max_odd {
    my $max;
    for my $num (@_) {
        next unless $num % 2;
        $max = $num unless defined $max;
        $max = $num if $num > $max;
    }
    return defined $max ? $max : "No odd number found\n";    # this co
+uld be replaced with if conditional statements if needed
}
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