import sys
input = sys.stdin.readline
sys.setrecursionlimit(10 ** 7)

n, x = map(int, input().split())

ans = 0
ans += n

l1, l2 = min(n - x, x), max(n - x, x)
while True:
    if l1 == l2:
        ans += l1
        break
    else:
        ans += (l1 * 2)
        l1, l2 = min(l1, l2 -l1), max(l1, l2 - l1)

print(ans)
