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 (3.8.2) (judge verdict: Accepted)

def main():
    abc = sorted(list(map(int, input().split())))

    cnt = 0
    while True:
        if abs(abc[2] - abc[0]) <= 1 and abs(abc[2] - abc[0]) <= 1:
            break
        abc[0] += 2
        abc = sorted(abc)
        cnt += 1
    ans = cnt
    if abc[0] == abc[1] and abc[1] == abc[2]:
        ans = cnt
    elif abc[2] == abc[1]:
        ans += 2
    elif abc[0] == abc[1]:
        ans += 1
    print(ans)


if __name__ == "__main__":
    main()