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 Go (1.6) (judge verdict: Accepted)

package main

import (
	"fmt"
	"sort"
)

func main() {
	ns := make([]int, 3)
	fmt.Scan(&ns[0], &ns[1], &ns[2])
	sort.Ints(ns)

	switch {
	case ns[0]%2 == ns[1]%2 && ns[0]%2 == ns[2]%2:
		fmt.Println((ns[2]-ns[0])/2 + (ns[2]-ns[1])/2)
	case ns[2]%2 != ns[0]%2 && ns[2]%2 != ns[1]%2:
		fmt.Println((ns[2]-ns[0])/2 + (ns[2]-ns[1])/2 + 1)
	default:
		fmt.Println((ns[2]-ns[0])/2 + (ns[2]-ns[1])/2 + 2)
	}
}