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 LL long long
#define int long long
inline LL read(){
	char c=getchar();while (c!='-'&&(c<'0'||c>'9'))c=getchar();
	LL k=0,kk=1;if (c=='-')c=getchar(),kk=-1;
	while (c>='0'&&c<='9')k=k*10+c-'0',c=getchar();return kk*k;
}using namespace std;
void write(LL x){if (x<0)x=-x,putchar('-');if (x/10)write(x/10);putchar(x%10+'0');}
void writeln(LL x){write(x);puts("");}
int a,b,c,aa,aaa,aaaa,bb,bbb,bbbb,cc,ccc,cccc,ans;
signed main(){
	a=read();b=read();c=read();ans=1e9;
	for (int i=-100;i<=100;i++){
		aa=max((i-a+1)/2,0ll);aaa=a+aa*2;aaaa=aaa-i;
		bb=max((i-b+1)/2,0ll);bbb=b+bb*2;bbbb=bbb-i;
		cc=max((i-c+1)/2,0ll);ccc=c+cc*2;cccc=ccc-i;
		ans=min(ans,aa+aaaa+bb+bbbb+cc+cccc);
	}writeln(ans);
}