n = int(input())
lines = []
for _ in range(n):
    a, b = map(int, input().split())
    lines.append((a, b))

def compute_f(x):
    if x <= 0:
        return float('inf')
    max_val = -float('inf')
    min_val = float('inf')
    for a, b in lines:
        val = a + b * x
        if val > max_val:
            max_val = val
        if val < min_val:
            min_val = val
    return max_val - min_val

low = 1
high = 10**18

while low < high:
    mid = (low + high) // 2
    current = compute_f(mid)
    next_val = compute_f(mid + 1)
    if current <= next_val:
        high = mid
    else:
        low = mid + 1

print(low)