def int_ternary_search(f, lo: int, hi: int) -> int:
    """区間 [lo, hi] で f(x) が最小となる整数 x を返す"""
    l = lo
    r = hi
    while r - l > 3:
        m1 = l + (r - l) // 3
        m2 = r - (r - l) // 3
        if f(m1) > f(m2):
            l = m1
        else:
            r = m2

    ind = l
    best = f(l)
    for i in range(l, r+1):
        v = f(i)
        if v < best:
            best = v
            ind = i

    return ind


INF = 1 << 60
N = int(input())
xs = []
for _ in range(N):
    a, b = map(int, input().split())
    xs.append((a, b))


def f(x):
    ma = -INF
    mi = INF
    for a, b in xs:
        ma = max(ma, a + b * x)
        mi = min(mi, a + b * x)

    return ma - mi


ans = int_ternary_search(f, 1, INF)
print(ans)