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 C++14 (GCC 5.4.1) (judge verdict: Accepted)

#include <iostream>
using namespace std;

int main(){
	int a, b, c;
	cin >> a >> b >> c;
	int x = max(max(a, b), c), ans = 0;
	while (a + 2 <= x)
		a += 2, ++ ans;
	while (b + 2 <= x)
		b += 2, ++ ans;
	while (c + 2 <= x)
		c += 2, ++ ans;
	int cnt = 0;
	if (a == x)
		++ cnt;
	if (b == x)
		++ cnt;
	if (c == x)
		++ cnt;
	if (cnt == 3)
		cout << ans << endl;
	else if (cnt == 2)
		cout << ans + 2 << endl;
	else if (cnt == 1)
		cout << ans + 1 << endl;
	return 0;
}