Memory is now interested in the de-evolution of objects, specifically triangles. He starts with an equilateral triangle of side length x, and he wishes to perform operations to obtain an equilateral triangle of side length y.

In a single second, he can modify the length of a single side of the current triangle such that it remains a non-degenerate triangle (triangle of positive area). At any moment of time, the length of each side should be integer.

What is the minimum number of seconds required for Memory to obtain the equilateral triangle of side length y?

Input

The first and only line contains two integers x and y (3 ≤ y < x ≤ 100 000) — the starting and ending equilateral triangle side lengths respectively.

Output

Print a single integer — the minimum number of seconds required for Memory to obtain the equilateral triangle of side length y if he starts with the equilateral triangle of side length x.

Examples

Input

6 3


Output

4


Input

8 5


Output

3


Input

22 4


Output

6

Note

In the first sample test, Memory starts with an equilateral triangle of side length 6 and wants one of side length 3. Denote a triangle with sides a, b, and c as (a, b, c). Then, Memory can do <image>.

In the second sample test, Memory can do <image>.

In the third sample test, Memory can do: <image>

<image>.
	import java.util.*;
import java.io.*;
public class Equi1 {
	public static void main(String args[])
	{
		InputReader in=new InputReader(System.in);
		int x=in.readInt();
		int y=in.readInt();
		int a1=y;
		int a2=y;
		int a3=y;
		
		int i,j,count=0;
		while(true)
		{
			if(a1>=x && a2>=x && a3>=x)
			{
				System.out.println(count);
				break;
			}
			
				//System.out.println("i m in");
				
				count++;
				if(count%3==1)
				{
					//System.out.println("i m in 1");
					a1= a2+a3-1;
				}
				if(count%3==2)
				{
					//System.out.println("i m in 1");
					a2= a1+a3-1;
				}
				if(count%3==0)
				{
					//System.out.println("i m in 1");
					a3= a1+a2-1;
				}
				
					
			}
			
			//System.out.println(i+" : "+arr[i]);
		}
		
		
		
		
	}

class InputReader {
 
		private InputStream stream;
		private byte[] buf = new byte[1024];
		private int curChar;
		private int numChars;
		private SpaceCharFilter filter;
 
		public InputReader(InputStream stream) {
			this.stream = stream;
		}
 
		public int read() {
			if (numChars == -1)
				throw new InputMismatchException();
			if (curChar >= numChars) {
				curChar = 0;
				try {
					numChars = stream.read(buf);
				} catch (IOException e) {
					throw new InputMismatchException();
				}
				if (numChars <= 0)
					return -1;
			}
			return buf[curChar++];
		}
 
		public int readInt() {
			int c = read();
			while (isSpaceChar(c))
				c = read();
			int sgn = 1;
			if (c == '-') {
				sgn = -1;
				c = read();
			}
			int res = 0;
			do {
				if (c < '0' || c > '9')
					throw new InputMismatchException();
				res *= 10;
				res += c - '0';
				c = read();
			} while (!isSpaceChar(c));
			return res * sgn;
		}
 
		public String readString() {
			int c = read();
			while (isSpaceChar(c))
				c = read();
			StringBuilder res = new StringBuilder();
			do {
				res.appendCodePoint(c);
				c = read();
			} while (!isSpaceChar(c));
			return res.toString();
		}
 
		public boolean isSpaceChar(int c) {
			if (filter != null)
				return filter.isSpaceChar(c);
			return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
		}
 
		public String next() {
			return readString();
		}
 
		public interface SpaceCharFilter {
			public boolean isSpaceChar(int ch);
		}
	}
 
class OutputWriter {
		private final PrintWriter writer;
 
		public OutputWriter(OutputStream outputStream) {
			writer = new PrintWriter(new BufferedWriter(new OutputStreamWriter(outputStream)));
		}
 
		public OutputWriter(Writer writer) {
			this.writer = new PrintWriter(writer);
		}
 
		public void print(Object...objects) {
			for (int i = 0; i < objects.length; i++) {
				if (i != 0)
					writer.print(' ');
				writer.print(objects[i]);
			}
		}
 
		public void printLine(Object...objects) {
			print(objects);
			writer.println();
		}
 
		public void close() {
			writer.close();
		}
 
		public void flush() {
			writer.flush();
		}
 
		}
 
class IOUtils {
 
		public static int[] readIntArray(InputReader in, int size) {
			int[] array = new int[size];
			for (int i = 0; i < size; i++)
				array[i] = in.readInt();
			return array;
		}
 
		}
	


