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 Scala (2.11.7) (judge verdict: Accepted)

object Main extends App {
  val sc = new java.util.Scanner(System.in)
  val A = sc.nextInt
  val B = sc.nextInt
  val C = sc.nextInt
  val X = Array(A, B, C).sorted

  val cntCA = (X(2) - X(0)) / 2
  val cntCB = (X(2) - X(1)) / 2

  val Y = Array(X(2), X(1) + cntCB * 2, X(0) + cntCA * 2)

  val cnt = Y.count(_ == X(2))

  if (cnt == 3) {
    println(cntCA + cntCB)
  } else if  (cnt == 2) {
    println(cntCA + cntCB + 2)
  } else {
    println(cntCA + cntCB + 1)
  }


}