#include <iostream>
#include <stdio.h>
using namespace std;



int
main ()
{


int a, b, c, count = 0;


cin >> a >> b >> c;


if (c - b == 1 && b - a == 1)

    {


cout << 0;


}


  else

    {


count = 0;


while (abs (a - b) != 1 || abs (a - c) != 1 || abs (b - c) != 1)
	  {


if (a < b && a < c && b - c != 1 && b - c != 1)

	      {


if ((b + c) % 2 == 0)

		  {


a = (b + c) / 2;


}


		else

		  {


a = (b + c) / 2 + 1;


}


count++;


}


	    else if (a > b && a > c && b - c != 1 && b - c != 1)

	      {


if ((b + c) % 2 == 0)

		  {


a = (b + c) / 2;


}


		else

		  {


a = (b + c) / 2 - 1;


}


count++;


}


	    else if (c > b && c > a && b - a != 1 && a - b != 1)

	      {


if ((b + a) % 2 == 0)

		  {


c = (b + a) / 2;


}


		else

		  {


c = (b + a) / 2 - 1;


}


count++;


}


	    else if (c < b && c < a && b - a != 1 && a - b != 1)

	      {


if ((b + a) % 2 == 0)

		  {


c = (b + a) / 2;


}


		else

		  {


c = (b + a) / 2 + 1;


}


count++;


}


	    else if (b > c && b > a && c - a != 1 && a - c != 1)

	      {


if ((c + a) % 2 == 0)

		  {


b = (c + a) / 2;


}


		else

		  {


b = (c + a) / 2 - 1;


}


count++;


}


	    else if (b < c && b < a && c - a != 1 && a - c != 1)

	      {


if ((c + a) % 2 == 0)

		  {


b = (c + a) / 2;


}


		else

		  {


b = (c + a) / 2 + 1;


}


count++;


}


cout << count;



}