/**
_ _ __ _ _ _ _ _ _
|a ||t ||o d | |o |
| __ _| | _ | __| _ |
| __ |/_ | __ /__\ / _\|
**/
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int N_MAX = 100000;
int N;
int X[N_MAX + 2], Y[N_MAX + 2];
int order[N_MAX + 2];
unordered_map <int, deque <int>> D1, D2;
int min_len[N_MAX + 2];
int dir[N_MAX + 2];
priority_queue <pair <int, int>> q;
/*
1\ /0
x
2/ \3
*/
void go (int i) {
if (dir[i] == 0 || dir[i] == 3) {
int d = X[i] - Y[i];
while (D1[d].empty() == false) {
int j = D1[d].back();
if (min_len[j] != -1) {
D1[d].pop_back();
} else if (X[i] + min_len[i] <= X[j]) {
D1[d].pop_back();
min_len[j] = X[j] - X[i];
dir[j] = (dir[i] == 0 ? 1 : 2);
q.push({-min_len[j], j});
} else {
break;
}
}
}
if (dir[i] == 1 || dir[i] == 0) {
int d = X[i] + Y[i];
while (D2[d].empty() == false) {
int j = D2[d].front();
if (min_len[j] != -1) {
D2[d].pop_front();
} else if (X[i] - min_len[i] >= X[j]) {
D2[d].pop_front();
min_len[j] = X[i] - X[j];
dir[j] = (dir[i] == 1 ? 2 : 3);
q.push({-min_len[j], j});
} else {
break;
}
}
}
if (dir[i] == 2 || dir[i] == 1) {
int d = X[i] - Y[i];
while (D1[d].empty() == false) {
int j = D1[d].front();
if (min_len[j] != -1) {
D1[d].pop_front();
} else if (X[i] - min_len[i] >= X[j]) {
D1[d].pop_front();
min_len[j] = X[i] - X[j];
dir[j] = (dir[i] == 2 ? 3 : 0);
q.push({-min_len[j], j});
} else {
break;
}
}
}
if (dir[i] == 3 || dir[i] == 2) {
int d = X[i] + Y[i];
while (D2[d].empty() == false) {
int j = D2[d].back();
if (min_len[j] != -1) {
D2[d].pop_back();
} else if (X[i] + min_len[i] <= X[j]) {
D2[d].pop_back();
min_len[j] = X[j] - X[i];
dir[j] = (dir[i] == 3 ? 0 : 1);
q.push({-min_len[j], j});
} else {
break;
}
}
}
}
int main () {
ios_base::sync_with_stdio(false);
cin.tie(0);
cin >> N;
for (int i = 1; i <= N; i++) {
cin >> X[i] >> Y[i];
}
iota(order + 1, order + N + 1, 1);
sort(order + 1, order + N + 1, [&] (const int &i, const int &j) {
return X[i] < X[j];
});
int answer = 0;
for (int d : {0, 1, 2, 3}) {
for (int k = 1; k <= N; k++) {
int i = order[k];
D1[X[i] - Y[i]].push_back(i);
D2[X[i] + Y[i]].push_back(i);
}
fill(min_len + 1, min_len + N + 1, -1);
min_len[1] = 0;
dir[1] = d; go(1);
while (q.empty() == false) {
int i = q.top().second; q.pop();
go(i);
}
int cnt = 0;
for (int i = 1; i <= N; i++) {
cnt += (min_len[i] != -1);
}
answer = max(answer, cnt);
D1.clear(); D2.clear();
}
cout << answer << "\n";
return 0;
}
