Snuke is conducting an optical experiment using mirrors and his new invention, the rifle of Mysterious Light.

Three mirrors of length N are set so that they form an equilateral triangle. Let the vertices of the triangle be a, b and c.

Inside the triangle, the rifle is placed at the point p on segment ab such that ap = X. (The size of the rifle is negligible.) Now, the rifle is about to fire a ray of Mysterious Light in the direction of bc.

The ray of Mysterious Light will travel in a straight line, and will be reflected by mirrors, in the same ways as "ordinary" light. There is one major difference, though: it will be also reflected by its own trajectory as if it is a mirror! When the ray comes back to the rifle, the ray will be absorbed.

The following image shows the ray's trajectory where N = 5 and X = 2.

btriangle.png

It can be shown that the ray eventually comes back to the rifle and is absorbed, regardless of the values of N and X. Find the total length of the ray's trajectory.

Constraints

* 2≦N≦10^{12}
* 1≦X≦N-1
* N and X are integers.

Input

The input is given from Standard Input in the following format:


N X


Output

Print the total length of the ray's trajectory.

Example

Input

5 2


Output

12
"""
def solve(N, X):
	xmax = ymax = zmax = N
	xmin = ymin = zmin = 0

	org = [N-X, X, 0]
	pos = [N-X, X, 0]
	dir = (0, -1, 1)
	ans = 0

	while True:
		if dir == (0,-1,1):
			if pos[1]-ymin < zmax-pos[2]:
				d = pos[1]-ymin
				pos[1] -= d
				pos[2] += d
				dir = (-1,1,0)
				xmax = pos[0]
			else:
				d = zmax-pos[2]
				pos[1] -= d
				pos[2] += d
				dir = (1,0,-1)
				xmin = pos[0]
		elif dir == (1,0,-1):
			if pos[2]-zmin < xmax-pos[0]:
				d = pos[2]-zmin
				pos[2] -= d
				pos[0] += d
				dir = (0,-1,1)
				ymax = pos[1]
			else:
				d = xmax-pos[0]
				pos[2] -= d
				pos[0] += d
				dir = (-1,1,0)
				ymin = pos[1]
		elif dir == (-1,1,0):
			if pos[0]-xmin < ymax-pos[1]:
				d = pos[0]-xmin
				pos[0] -= d
				pos[1] += d
				dir = (1,0,-1)
				zmax = pos[2]
			else:
				d = ymax-pos[1]
				pos[0] -= d
				pos[1] += d
				dir = (0,-1,1)
				zmin = pos[2]
		else:
			print "error"
			break

		ans += d

		if pos==org:
			break
	return ans

for N in range(2, 17):
	print N,
	for X in range(1, N):
		print solve(N, X)/3,
	print

"""

import fractions
N, X = map(int, raw_input().split())
g = fractions.gcd(N, X)
print 3*g*(N/g-1)
