#agc014a. [agc014_a]Cookie Exchanges

[agc014_a]Cookie Exchanges

Problem Statement

Takahashi, Aoki and Snuke love cookies. They have AA, BB and CC cookies, respectively. Now, they will exchange those cookies by repeating the action below:

  • Each person simultaneously divides his cookies in half and gives one half to each of the other two persons.

This action will be repeated until there is a person with odd number of cookies in hand.

How many times will they repeat this action? Note that the answer may not be finite.

Constraints

  • 1A,B,C1091 ≤ A,B,C ≤ 10^9

Input

Input is given from Standard Input in the following format:

AA BB CC

Output

Print the number of times the action will be performed by the three people, if this number is finite. If it is infinite, print -1 instead.


Sample Input 1

4 12 20

Sample Output 1

Initially, Takahashi, Aoki and Snuke have 44, 1212 and 2020 cookies. Then,

  • After the first action, they have 1616, 1212 and 88.
  • After the second action, they have 1010, 1212 and 1414.
  • After the third action, they have 1313, 1212 and 1111.

Now, Takahashi and Snuke have odd number of cookies, and therefore the answer is 33.


Sample Input 2

14 14 14

Sample Output 2

-1

Sample Input 3

454 414 444

Sample Output 3