Problem:
Score : 300 points

Problem Statement

Takahashi, Aoki and Snuke love cookies. They have A, B and C 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

1 ≤ A,B,C ≤ 10^9

Input

Input is given from Standard Input in the following format:

A B C

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

3

Initially, Takahashi, Aoki and Snuke have 4, 12 and 20 cookies. Then,

After the first action, they have 16, 12 and 8.

After the second action, they have 10, 12 and 14.

After the third action, they have 13, 12 and 11.

Now, Takahashi and Snuke have odd number of cookies, and therefore the answer is 3.

Sample Input 2

14 14 14

Sample Output 2

-1

Sample Input 3

454 414 444

Sample Output 3

1

Solution in Java8 (OpenJDK 1.8.0) (judge verdict: Accepted)

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.HashSet;

class Main {
	public static void main(String args[]) throws IOException {
		BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
		Solver solver = new Solver();
		solver.init();
		solver.readHead(in.readLine());
		// for (; solver.hasNext();) {
		// solver.readBody(in.readLine());
		// }
	}
}

class Solver {
	int N;
	int cnt;

	public void init() {
		N = 0;
		cnt = 0;
	}

	private class Cookie {
		int min;
		int mid;
		int max;

		Cookie(int a, int b, int c) {
			min = a;
			mid = b;
			max = c;
			if (min > mid) {
				int bk = mid;
				mid = min;
				min = bk;
			}
			if (mid > max) {
				int bk = max;
				max = mid;
				mid = bk;
			}
			if (min > mid) {
				int bk = mid;
				mid = min;
				min = bk;
			}
		}

		@Override
		public int hashCode() {
			final int prime = 31;
			int result = 1;
			result = prime * result + getOuterType().hashCode();
			result = prime * result + max;
			result = prime * result + mid;
			result = prime * result + min;
			return result;
		}

		@Override
		public boolean equals(Object obj) {
			if (this == obj)
				return true;
			if (obj == null)
				return false;
			if (getClass() != obj.getClass())
				return false;
			Cookie other = (Cookie) obj;
			if (!getOuterType().equals(other.getOuterType()))
				return false;
			if (max != other.max)
				return false;
			if (mid != other.mid)
				return false;
			if (min != other.min)
				return false;
			return true;
		}

		private Solver getOuterType() {
			return Solver.this;
		}
	}

	public void readHead(String str) {
		String[] strArr = str.split(" ");
		int a = Integer.parseInt(strArr[0]);
		int b = Integer.parseInt(strArr[1]);
		int c = Integer.parseInt(strArr[2]);
		HashSet<Cookie> cookieSet = new HashSet<Cookie>();
		int cnt = 0;
		for (; a % 2 == 0 && b % 2 == 0 && c % 2 == 0;) {
			Cookie cookie = new Cookie(a, b, c);
			if (cookieSet.contains(cookie)) {
				cnt = -1;
				break;
			}
			cookieSet.add(cookie);
			cnt++;
			int ah = a / 2;
			int bh = b / 2;
			int ch = c / 2;
			a = bh + ch;
			b = ah + ch;
			c = ah + bh;
		}
		System.out.println(cnt);
	}

	public boolean hasNext() {
		return cnt < N;
	}

	public void readBody(String str) {
		// System.out.println(str);
		cnt++;
	}
}