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)

import numpy as np

def input_numbers():
    temp = list(map(int, input().split()))
    return temp

def GCD(a, b):
    if(a < b):
        temp = a
        a = b
        b = temp
    a = a % b
    if(a == 0):
        return b
    else:
        return GCD(a, b)

numbers = input_numbers()

numbers.sort()

count = 0

count += numbers[2] - numbers[1]
numbers[0] += numbers[2] - numbers[1]
numbers[1] = numbers[2]

diff = numbers[2] - numbers[0]

if(diff % 2 == 0):
    count += (diff // 2)

else:
    numbers[1] += 1
    numbers[2] += 1
    count += 1

    diff = numbers[2] - numbers[0]
    count += (diff // 2)

print(count)