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>
using namespace std;

#define ll long long
#define rep(i, n) for(ll i = 0; i < (n); i++)
ll MOD = 1e9 + 7;
int INF = 1 << 30;
ll INFL = 1LL << 60;

int main() {
    ll A,B,C;
    cin >>  A >> B >> C;
    ll sum = 0;
    sum = A + B + C;
    ll submax = 0;
    submax = max(A,B);
    submax = max(submax,C);
    if(sum % 2 == 0){
        if(submax%2 == 0) cout << (submax*3 - sum)/2 <<endl;
        else {
            cout << ((submax+1)*3  - sum)/2 <<endl;
        }
    }
    else {
        if(submax%2 == 0) cout << ((1+submax)*3 - sum)/2 <<endl;
        else {
            cout << (submax*3  - sum)/2 <<endl;
        }
    }
}