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-----
2 5 4

-----Sample Output-----
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.

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