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: Wrong Answer)

# C
a = list(map(int, input().split()))
a.sort()
all_odd = True
for i in range(3):
    if a[i] % 2 == 0:
        all_odd = False
max_a = a[2]
ans = 0
if all_odd:
    for i in range(2):
        ans += (max_a - a[i])/2
elif max_a % 2 == 1:
    for i in range(2):
        ans += (max_a-1 - a[i])/2
    ans += 1
else:
    for i in range(2):
        if a[i] % 2 == 0:
            ans += (max_a - a[i])/2
        else:
            ans += (max_a-1 - a[i])/2
    ans += 2
print(int(ans))