Problem:
Score : 300 points

Problem Statement

You are given three integers A, B and C. Find the minimum number of operations required to make A, B and C all equal by repeatedly performing the following two kinds of operations in any order:

Choose two among A, B and C, then increase both by 1.

Choose one among A, B and C, then increase it by 2.

It can be proved that we can always make A, B and C all equal by repeatedly performing these operations.

Constraints

0 \leq A,B,C \leq 50

All values in input are integers.

Input

Input is given from Standard Input in the following format:

A B C

Output

Print the minimum number of operations required to make A, B and C all equal.

Sample Input 1

2 5 4

Sample Output 1

2

We can make A, B and C all equal by the following operations:

Increase A and C by 1. Now, A, B, C are 3, 5, 5, respectively.

Increase A by 2. Now, A, B, C are 5, 5, 5, respectively.

Sample Input 2

2 6 3

Sample Output 2

5

Sample Input 3

31 41 5

Sample Output 3

23

Solution in Perl (v5.18.2) (judge verdict: Accepted)

use v5.18;
use warnings;
use List::Util qw( min );
sub read_line { chomp(my $str = <STDIN>); $str }
sub splited_read_line { split / /, read_line }
my @nums = sort { $b <=> $a } splited_read_line;
my ($max, $middle, $min) = @nums;
my $one_conut = $max - $middle;
$middle += $one_conut, $min += $one_conut;
my $two_count = $max - $min;
$one_conut++ if $two_count % 2;
$two_count = int( ($two_count + 1)  / 2);
say $one_conut + $two_count;