/* -*- coding: utf-8 -*-
 *
 * 1864.cc:  No.1864 Shortest Paths Counting - yukicoder
 */

#include<cstdio>
#include<vector>
#include<algorithm>
 
using namespace std;

/* constant */

const int MAX_N = 200000;
const int MOD = 998244353;

/* typedef */

typedef long long ll;
typedef pair<int,int> pii;

template <typename T>
struct BIT {
  int n;
  vector<T> bits;
  
  BIT() {}
  BIT(int _n) { init(_n); }

  void init(int _n) {
    n = _n;
    bits.resize(n + 1, 0);
  }

  T sum(int x) {
    x = min(x, n);
    T s = 0;
    while (x > 0) {
      s = (s + bits[x]) % MOD;
      x -= (x & -x);
    }
    return s;
  }

  void add(int x, T v) {
    if (x <= 0) return;
    while (x <= n) {
      bits[x] = (bits[x] + v) % MOD;
      x += (x & -x);
    }
  }
};

/* global variables */

int xs[MAX_N], ys[MAX_N], uys[MAX_N];
pii ps[MAX_N];
BIT<int> bit;

/* subroutines */

bool cmppii(const pii &a, const pii &b) {
  return a.first < b.first || (a.first == b.first && a.second > b.second);
}

/* main */

int main() {
  int n;
  scanf("%d", &n);

  for (int i = 0; i < n; i++) {
    int xi, yi;
    scanf("%d%d", &xi, &yi);
    xs[i] = xi + yi, ys[i] = xi - yi;
  }

  bool xrv = (xs[0] > xs[n - 1]);
  bool yrv = (ys[0] > ys[n - 1]);
  for (int i = 0; i < n; i++) {
    if (xrv) xs[i] = -xs[i];
    if (yrv) ys[i] = -ys[i];
  }

  int x0 = xs[0], y0 = ys[0];
  int gx = xs[n - 1] - x0, gy = ys[n - 1] - y0;

  int m = 0;
  for (int i = 0; i < n; i++) {
    int xi = xs[i] - x0, yi = ys[i] - y0;
    if (0 <= xi && xi <= gx && 0 <= yi && yi <= gy) ps[m++] = pii(xi, yi);
  }
  if (m > 2) sort(ps + 1, ps + m - 1);
  //for (int i = 0; i < m; i++) printf("%d,%d ", ps[i].first, ps[i].second);
  //putchar('\n');

  for (int i = 0; i < m; i++) uys[i] = ps[i].second;
  sort(uys, uys + m);
  int k = unique(uys, uys + m) - uys;

  bit.init(k);
  bit.add(1, 1);
  for (int i = 1; i < m - 1; i++) {
    int yi = lower_bound(uys, uys + k, ps[i].second) - uys;
    int di = bit.sum(yi + 1);
    bit.add(yi + 1, di);
  }

  int sum = bit.sum(k);
  printf("%d\n", sum);
  return 0;
}