n=int(input())
x_online_file = [0]*(200005)
for _ in range(n):
    x, r = (int(a) for a in input().split())
    x_online_file[x-r+100000] += 1
    x_online_file[x+r+1+100000] -= 1

for i in range(1,200005):
    x_online_file[i] += x_online_file[i-1]
print(max(x_online_file))