n=int(input())
a=[]
for _ in range(n):
    x,r=map(int,input().split())
    a.append((x-r,1))
    a.append((x+r,-1))
a.sort()
i=0
ans=0
cur=0
while i<n*2:
    b=a[i][0]
    while i<n*2 and a[i][0]==b:
        cur+=a[i][1]
        i+=1
    ans=max(ans,cur)
print(ans)