N = int(input())
cnd = [0] * N
c = [0] * N
for i in range(N):
    s = input().split()
    M = int(s[1]) % int(s[0])
    for j in range(N):
        if M == cnd[j] and M != 0:
            c[j] += 1
    cnd[i] = M
mMax = 0
d = 0
for i in range(N):
    if c[i] > mMax:
        mMax = c[i]
        d = i
    if c[i] == mMax:
        if cnd[i] > cnd[d]:
            d = i
print(cnd[d])