n = int(input())
accumA = [0 for _ in range(4 * 10**5 + 10)]
for _ in range(n):
    x, r = map(int, input().split())
    accumA[x - r + 2 * 10**5] += 1
    accumA[x + r + 2 * 10**5] -= 1
for i in range(4 * 10**5 + 5):
    accumA[i + 1] += accumA[i]
print(max(accumA))