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: Wrong Answer)

#include<iostream>
#include<algorithm>

using namespace std;

int main() {

	int A = 0;
	int B = 0;
	int C = 0;
	int maxnum = 0;

	cin >> A >> B >> C;

	maxnum = max({ A, B, C });

	if (A % 2 == B % 2 && B % 2 == C % 2) {

		cout << (maxnum * 3 - A - B - C) / 2 << endl;

	}
	else {

		if (A % 2 == B % 2) {

			A++;
			B++;

		}
		else {

			if (A % 2 == C % 2) {

				A++;
				C++;

			}
			else {

				B++;
				C++;

			}

		}

		cout << 1 + (maxnum * 3 - A - B - C) / 2 << endl;

	}

	return 0;

}