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 sys

def solve():
    input = sys.stdin.readline
    L = [int(i) for i in input().split()]
    count = 0
    L.sort()
    addMin = (L[2] - L[0]) // 2  
    addMid = (L[2] - L[1]) // 2
    count = addMin + addMid
    L[0] += addMin * 2
    L[1] += addMid * 2
    if L[0] < L[2] and L[1] < L[2]: print(count + 1)
    elif L[0] == L[1] == L[2]: print(count)
    else: print(count + 2)
    #print(L)

    return 0

if __name__ == "__main__":
    solve()