import sys
input=lambda: sys.stdin.readline().rstrip()
D1,D2=dict(),dict()
for i in range(10):
	for j in range(10):
		D1[(i,j)]=2**i*5**j
		D2[2**i*5**j]=(i,j)

x1,x2=map(int,input().split())
while True:
	if 2*x1==x2 or 5*x1==x2 or x1==2*x2 or x1==5*x2:
		print(x2,flush=True)
		sys.exit()
	else:
		i1,j1=D2[x1]
		i2,j2=D2[x2]
		if (i1+j1)%2!=(i2+j2)%2:
			if abs(i1-i2)>abs(j1-j2):
				if i1<i2:
					x1=D1[(i1+1,j1)]
				else:
					x1=D1[(i1-1,j1)]
			else:
				if j1<j2:
					x1=D1[(i1,j1+1)]
				else:
					x1=D1[(i1,j1-1)]
		else:
			if i1==7 and j1==9:
				x1=10**9
			elif i1==7:
				x1=D1[(i1,j1+1)]
			else:
				x1=D1[(i1+1,j1)]
		print(x1,flush=True)
		x2=int(input())
		if x1==x2:
			sys.exit()