#include <stdio.h>
#include <bits/stdc++.h>
#include <atcoder/all>
using namespace atcoder;
using mint = modint998244353;
using namespace std;
#define rep(i,n) for(int i=0;i<(n);i++)
#define Inf 1000000000
int n;
vector<long long> x,y;

mint op(mint a,mint b){
	return a+b;
}

mint e(){
	return 0;
}

int main(){
	
	
	cin>>n;
	x.resize(n),y.resize(n);
	rep(i,n){
		cin>>x[i]>>y[i];
		long long t = x[i]+y[i];
		y[i] = x[i]-y[i];
		x[i] = t;
	}
	
	
	
	for(int i=n-1;i>=0;i--){
		y[i] -= y[0];
		x[i] -= x[0];
	}
	rep(i,n){
		if(y.back()<0)y[i] *= -1;
		if(x.back()<0)x[i] *= -1;
	}
	vector<int> t;
	rep(i,n){
		t.push_back(x[i]);
		t.push_back(y[i]);
		
	}
	sort(t.begin(),t.end());
	t.erase(unique(t.begin(),t.end()),t.end());
	rep(i,n){
		x[i] = distance(t.begin(),lower_bound(t.begin(),t.end(),x[i]));
		y[i] = distance(t.begin(),lower_bound(t.begin(),t.end(),y[i]));
	}
	
	vector<int> ind(n);
	rep(i,n)ind[i] = i;
	
	sort(ind.begin(),ind.end(),[&](int a,int b){
		return make_pair(x[a],y[a])<make_pair(x[b],y[b]);
	});
	
	
	segtree<mint,op,e> seg(t.size());
	mint ans;
	rep(i,n){
		if(ind[i]==0){
		///	seg.set(y[ind[i]],1);
		}
		else if(ind[i]==n-1){
			//ans = seg.prod(0,y[ind[i]]+1);
		}
		else{
		//	mint tt = seg.prod(0,y[ind[i]]+1);
			//seg.set(y[ind[i]],seg.get(y[ind[i]])+tt);
		}
	}
	cout<<ans.val()<<endl;
	
	
	return 0;
}