in reply to John Guttag's book - 2nd exercise. My attempt in Perl.

Here's a solution using only if/else, <, and %. No ||, &&, and, or, =, or anything else allowed.
It's sort of silly for something that is a one-liner in normal perl.

( note: the comments following open braces show which variables are still valid at this point.) 

#!/usr/bin/perl

# http://perlmonks.org/?node_id=1190754

use strict;
use warnings;

my ($x, $y, $z) = (-11,-13,4);

if( $x % 2 )
  { # xyz
  if( $y % 2 )
    { # xyz
    if( $x < $y )
      { # yz
      if( $z % 2 )
        { # yz
        if( $y < $z )
          { # z
          print "z of $z is the biggest odd number\n";
          }
        else
          { # y
          print "y of $y is the biggest odd number\n";
          }
        }
      else
        { # y
        print "y of $y is the biggest odd number\n";
        }
      }
    else
      { # xz
      if( $z % 2 )
        { # xz
        if( $x < $z )
          { # z
          print "z of $z is the biggest odd number\n";
          }
        else
          { # x
          print "x of $x is the biggest odd number\n";
          }
        }
      else
        { # x
        print "x of $x is the biggest odd number\n";
        }
      }
    }
  else
    { # xz
    if( $z % 2 )
      { # xz
      if( $x < $z )
        { # z
        print "z of $z is the biggest odd number\n";
        }
      else
        { # x
        print "x of $x is the biggest odd number\n";
        }
      }
    else
      { # x
      print "x of $x is the biggest odd number\n";
      }
    }
  }
else
  { # yz
  if( $y % 2 )
    { # yz
    if( $z % 2 )
      { # yz
      if( $y < $z )
        { # z
        print "z of $z is the biggest odd number\n";
        }
      else
        { # y
        print "y of $y is the biggest odd number\n";
        }
      }
    else
      { # y
      print "y of $y is the biggest odd number\n";
      }
    }
  else
    { # z
    if( $z % 2 )
      { # z
      print "z of $z is the biggest odd number\n";
      }
    else
      { #
      print "All are even numbers\n";
      }
    }
  }

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Replies are listed 'Best First'.
Re^2: John Guttag's book - 2nd exercise. My attempt in Perl.
by Anonymous Monk on May 22, 2017 at 22:26 UTC
    Now write one that checks 26 vars: $a .. $z

    Also, nested ifs count as ORs and ANDs :D

[reply]

      No, they don't.

[reply]
        What kind of troll do u think u r? 
        $a = 1;
$b = 0;

print "OR\n" if $a or $b;
print "AND\n" if $a and $b;

if ($a) {
    if ($b) {
        print "AND\n";
    } else {
        print "OR\n";
    }
} elsif ($b) {
    if ($a) {
        print "AND\n";
    } else {
        print "OR\n";
    }
}

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[reply]
[d/l]
Re^2: John Guttag's book - 2nd exercise. My attempt in Perl.
by Anonymous Monk on May 22, 2017 at 22:24 UTC
    I wish I could downvote this 100 times.
[reply]

      I'm just following the posted rules :)

      Let's see your solution following the posted rules...

[reply]
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