import sys
input = sys.stdin.readline

N = int(input())
imos = [0]*(4*10**5+1)

for _ in range(N):
    x, r = map(int, input().split())
    l = x-r+2*10**5
    r = x+r+2*10**5
    imos[l] += 1
    imos[r] -= 1

for i in range(1, 4*10**5+1):
    imos[i] += imos[i-1]

print(max(imos))