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 Ruby (2.7.1) (judge verdict: Accepted)

a, b, c = gets.to_s.split.map{|t|t.to_i}

o_num = 0
o_num += 1 if a.odd?
o_num += 1 if b.odd?
o_num += 1 if c.odd?

ans = 0
if o_num == 1
  
  ans += 1
  a += 1 if a.even?
  b += 1 if b.even?
  c += 1 if c.even?
  
elsif o_num == 2
  
  ans += 1
  a += 1 if a.odd?
  b += 1 if b.odd?
  c += 1 if c.odd?

end

x = [a, b, c].sort
m = x.max

ans += ( m - x[0] ) / 2
ans += ( m - x[1] ) / 2

puts ans