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";
      }
    }
  }

[download]

In reply to Re: John Guttag's book - 2nd exercise. My attempt in Perl. by tybalt89
in thread John Guttag's book - 2nd exercise. My attempt in Perl. by pritesh_ugrankar

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