while (1) {
    my  $first          = GetMeasurement('1st');
    my  $next_step      = GetMeasurement('2nd');
    my  $distance       = abs($next_step - $first);
    my  $gap            = $distance / 3;
    my  $gap_frac       = Fractionalize($gap);

    print "\nDistance between balusters: $gap_frac\"   ($gap)\n";

    my  $second         = $first    + $gap;       # Locate second hole
    my  $third          = $second   + $gap;       # Locate third hole
    my  $first_frac     = Fractionalize($first);  # Get fraction value
    my  $second_frac    = Fractionalize($second); # Get fraction value
    my  $third_frac     = Fractionalize($third);  # Get fraction value

    print "\nDrill 1st baluster hole at: $first_frac\"  ($first)\n";
    print   "Drill 2nd baluster hole at: $second_frac\"  ($second)\n";
    print   "Drill 3rd baluster hole at: $third_frac\"  ($third)\n\n";
}

exit;
#####################################################
# Get measurement to first hole on stair tread.
#####################################################
sub GetMeasurement {
    $position           = shift;
    print "Enter $position measurement.....: ";
    my $measurement     = <STDIN>;
    exit if $measurement =~ /q/i;                   # Terminate if 'q'
    chomp $measurement;
    if  ( $measurement =~ /(\d*)\s(\d*)\/(\d*)/ ) { 
          $measurement  = ${1} + ${2} / ${3};       
    }
    return $measurement;
}

#####################################################
# Convert a number with decimals to a fraction-scale: 32's of an inch
#####################################################
sub Fractionalize {
    my $number          = shift;                    # Get the number
    my @numbers         = split(/\./, $number);     # Get int&decimal
    my $modulus         = '.' . $numbers[1];        # Put decimal back
    my $x32             = ($modulus * 32);          # Multiply x 1/32"
    my $fraction        = Reduce($x32,32);          # Reduce fraction
    return "$numbers[0] $fraction";                 # Return fraction
}

#####################################################
# Reduce a fraction as far as possible (6/32 -> 3/16, 16/32 -> 1/2)
#####################################################
sub Reduce {
    my $divisor         = shift;                    # Get top 
    my $denominator     = shift;                    # Get bottom 
    $divisor            = int $divisor;    # Trim insignificat digits

  # Continue until either number is no longer divisible by 2
    while (1) {           
        unless (($divisor %2) or ($denominator %2)) { 
            $divisor    = $divisor     / 2;
            $denominator= $denominator / 2;
        } else { 
            last;
        }
    }
    return "$divisor/$denominator";
}
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