n = int(eval(input()))

X = []

for i in range(n):

  x, l = list(map(int, input().split()))

  X.append([x-l, x+l])

X.sort()

temp = X[0][1]

count = n

for i in range(1,n):

  if temp>X[i][0]:

    count -= 1

    temp = min(temp, X[i][1])

  else:

    temp = X[i][1]

print(count)
import sys

input = sys.stdin.readline

n = int(eval(input()))

X = []

for i in range(n):

  x, l = list(map(int, input().split()))

  X.append([x-l, x+l])

X.sort()

temp = X[0][1]

count = n

for i in range(1,n):

  if temp>X[i][0]:

    count -= 1

    temp = min(temp, X[i][1])

  else:

    temp = X[i][1]

print(count)

n = int(eval(input()))
X = []
for i in range(n):
    x, l = list(map(int, input().split()))
    X.append([x - l, x + l])
X.sort()
temp = X[0][1]
count = n
for i in range(1, n):
    if temp > X[i][0]:
        count -= 1
        temp = min(temp, X[i][1])
    else:
        temp = X[i][1]
print(count)

import sys

input = sys.stdin.readline
n = int(eval(input()))
X = []
for i in range(n):
    x, l = list(map(int, input().split()))
    X.append([x - l, x + l])
X.sort()
temp = X[0][1]
count = n
for i in range(1, n):
    if temp > X[i][0]:
        count -= 1
        temp = min(temp, X[i][1])
    else:
        temp = X[i][1]
print(count)

+import sys + +input = sys.stdin.readline