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>
#include<string>
using namespace std;
int main(){
   int A,B,C;
   cin>> A >> B >> C;
   int K;
   int d1,d2;
   if (A<B){
     K=A;
     A=B;
     B=K;
   }
   if (A<C){
     K=A;
     A=C;
     C=K;
   }
   d1=(A-B)%2;
   d2=(A-C)%2;
   if((d1==0)&&(d2==0)){
     cout << (A-B)/2+(A-C)/2;
   }
   if((d1==0)&&(d2==1)){
     cout << (A-B)/2+(A-C-1)/2+2;
   }
   if((d1==1)&&(d2==0)){
     cout << (A-B-1)/2+(A-C)/2+2;
   }
   if((d1==1)&&(d2==1)){
     cout << (A-B-1)/2+(A-C-1)/2+1;
   }
   return 0;
}