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() {
	ar := make([]int, 3)
	fmt.Scan(&ar[0], &ar[1], &ar[2])
	sum := 0
	if ar[0] == ar[1] && ar[1] == ar[2] {
		fmt.Println(sum)
		return
	}
	for {
		sort.Ints(ar)
		if ar[2]-ar[0] >= 2 {
			sum++
			ar[0] += 2
		} else {
			sum++
			ar[0]++
			ar[1]++
		}
		if ar[0] == ar[1] && ar[1] == ar[2] {
			fmt.Println(sum)
			return
		}
	}
}