n = int(input())

data = [0 for _ in range(pow(10,5)*4+1)]

for i in range(n):
    x, r = map(int, input().split())
    data[x-r+pow(10,5)*2] += 1
    data[x+r+pow(10,5)*2] -= 1

for i in range(len(data)-1):
    data[i+1] += data[i]

print(max(data))