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 <bits/stdc++.h>
#define int long long
using namespace std;
const int INF = 1LL << 60;
const int MOD = (int) 1e9 + 7;

signed main() {
    vector<int> v(3);
    cin >> v[0] >> v[1] >> v[2];
    sort(v.begin(), v.end());
    int cnt = 0;
    cnt += v[2] - v[1];
    v[0] += v[2] - v[1];
    v[1] = v[2];
    if ((v[1] - v[0]) % 2 == 0) {
        cnt += (v[1] - v[0]) / 2;
    }
    else {
        cnt += (v[1] - v[0]) / 2 + 2;
    }
    cout << cnt << "\n";
}