R,I=range,input
def J():
	a=[]
	for s in I().split():
		i=s.find('.')
		a+=[int(s+'0'*7)if i<0 else int(s[:i]+s[i+1:min(len(s),i+8)]+'0'*(8-len(s)+i))]
	return a
N=int(I())
x,y=J()
X,Y=x,y
for i in R(1,N):s,t=J();x,y,X,Y=min(x,s),min(y,t),max(X,s),max(Y,t)
X,Y=X-x,Y-y
z,w=J()
Z,W=z,w
for i in R(1,N):s,t=J();z,w,Z,W=min(z,s),min(w,t),max(Z,s),max(W,t)
Z,W=Z-z,W-w
print([Z/X,W/Y][X<Y])