def get(x):
    return max(a+b*x for a,b in ab) - min(a+b*x for a,b in ab)

n = int(input())
ab = [list(map(int,input().split())) for _ in range(n)]

l = 1
r = 2*10**9
cnt = 0
while r-l > 5:
    d = (r-l)//3
    m1 = l+d
    m2 = l+2*d
    if get(m1) <= get(m2):
        r = m2
    else:
        l = m1
    cnt += 1
    if cnt == 100: break

v = get(l)
c = l
for i in range(l,r):
    gi = get(i)
    if v > gi:
        v = gi
        c = i
print(c)