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.