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 Python (3.4.3) (judge verdict: Accepted)

A = list(map(int, input().split()))
 
even = 0
odd = 0
for a in A:
  if(a%2==0):
    even += 1
 
for i in range(len(A)):
  if(A[i]%2==0 and even == 2):
    A[i] += 1
  elif(A[i]%2==1 and even == 1):
    A[i] += 1
 
if(even == 2 or even == 1):
  ans = 1
else:
  ans = 0
 
for a in A:
  ans += (max(A) - a) // 2
 
print(ans)