#include <bits/stdc++.h>
using namespace std;
#define rep(i,n) for(int i = 0;i < (n);i++)
using ll = long long;
int mod = 998244353;
using P = pair<double,double>;
int LEN = 1 << 20;
vector<ll> seg(2*LEN,0);
void add(int ind,ll val){
  ind += LEN;
  seg[ind] += val;
  while(ind > 0){
    ind /= 2;
    seg[ind] = seg[ind*2] + seg[ind*2+1];
    seg[ind] %= mod;
  }
}
ll sum(int l,int r){
  l += LEN;
  r += LEN;
  ll ans = 0;
  while(l < r){
    if(l % 2 == 1)ans += seg[l++];
    l /= 2;
    if(r % 2 == 1)ans += seg[--r];
    r /= 2;
    ans %= mod;
  }
  return ans;
}
int main(){
  int n;
  cin >> n;
  vector<P> pos(n);
  rep(i,n){
    double x,y;
    cin >> x >> y;
    pos[i].first = (x + y)/2 + 1e9;
    pos[i].second = (x - y)/2 + 1e9;
  }
  if(pos[0].second > pos[n-1].second){
    rep(i,n){
      pos[i].second *= (-1);pos[i].second += 2e9;
    }
  }
  if(pos[0].first > pos[n-1].first){
    rep(i,n){
      pos[i].first *= (-1);pos[i].first += 2e9;
    }
  }
  vector<double> x(n),y(n);
  rep(i,n){
    x[i] = pos[i].first;
    y[i] = pos[i].second;
  }
  sort(x.begin(),x.end());
  sort(y.begin(),y.end());
  map<double,int> mpX,mpY;
  rep(i,n)mpX[x[i]] = lower_bound(x.begin(),x.end(),x[i]) - x.begin();
  rep(i,n)mpY[y[i]] = lower_bound(y.begin(),y.end(),y[i]) - y.begin();
  vector<tuple<int,int,int>> pos2(n);
  rep(i,n)pos2[i] = make_tuple(mpX[pos[i].first],mpY[pos[i].second],i);
  sort(pos2.begin(),pos2.end());
  int start,last;
  rep(i,n){
    int a,b,c;
    tie(a,b,c) = pos2[i];
    if(a == mpX[pos[0].first] && b == mpY[pos[0].second])start = i;
    if(a == mpX[pos[n-1].first] && b == mpY[pos[n-1].second])last = i;
  }
  vector<int> dp(n,0);
  for(int i = start;i <= last;i++){
    int a,b,c;
    tie(a,b,c) = pos2[i];
    if(i == start)dp[i] = 1;
    else dp[i] = sum(0,b+1);
    dp[i] %= mod;
    add(b,dp[i]);
  }
  cout << dp[last] << endl;
}