#include #include #include #include #include #include #include #include #include #include #include #include #include #define debug_value(x) cerr << "line" << __LINE__ << ":<" << __func__ << ">:" << #x << "=" << x << endl; #define debug(x) cerr << "line" << __LINE__ << ":<" << __func__ << ">:" << x << endl; template inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; } template inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; } using namespace std; typedef long long ll; template vector> vec2d(int n, int m, T v){ return vector>(n, vector(m, v)); } template vector>> vec3d(int n, int m, int k, T v){ return vector>>(n, vector>(m, vector(k, v))); } template void print_vector(vector v, char delimiter=' '){ if(v.empty()) { cout << endl; return; } for(int i = 0; i+1 < v.size(); i++) cout << v[i] << delimiter; cout << v.back() << endl; } const ll MOD = 998244353; class ModInt{ public: ll v; ModInt(ll _v = 0){ if(_v < 0) _v = (_v%MOD)+MOD; if(_v >= MOD) _v %= MOD; v = _v; } ModInt operator+(ll n){ return ModInt((v+n)%MOD); } ModInt operator-(ll n){ return ModInt((v-n+MOD)%MOD); } ModInt operator*(ll n){ if(n >= MOD) n %= MOD; return ModInt((v*n)%MOD); } ModInt operator/(ll n){ return ModInt((ModInt(n).inv()*v).v%MOD); } ModInt &operator+=(ll n){ v = (v+n)%MOD; return *this; } ModInt &operator-=(ll n){ v = (v-n+MOD)%MOD; return *this; } ModInt &operator*=(ll n){ v = (v*n+MOD)%MOD; return *this; } ModInt operator+(ModInt n){ return ModInt((v+n.v)%MOD); } ModInt operator-(ModInt n){ return ModInt((v-n.v+MOD)%MOD); } ModInt operator*(ModInt n){ return ModInt((v*n.v)%MOD); } ModInt operator/(ModInt n){ return ModInt((n.inv()*v).v%MOD); } ModInt &operator+=(ModInt n){ v = (v+n.v)%MOD; return *this; } ModInt &operator-=(ModInt n){ v = (v-n.v+MOD)%MOD; return *this; } ModInt &operator*=(ModInt n){ v = (v*n.v)%MOD; return *this; } bool operator==(ModInt n){ return v == n.v; } bool operator!=(ModInt n){ return v != n.v; } ModInt &operator=(ll n){ v = n%MOD; return *this; } ModInt inv(){ if(v == 1) return ModInt(1); else return ModInt(MOD-ModInt(MOD%v).inv().v*(MOD/v)%MOD); } }; ostream& operator<<(ostream& os, const ModInt& m){ os << m.v; return os; } istream & operator >> (istream &in, ModInt &m){ in >> m.v; return in; } ModInt pow(ModInt a, ll n) { assert(n >= 0); ModInt ans = 1; while (n > 0) { if (n&1) ans = ans*a; a = a*a; n >>= 1; } return ans; } template class Compress{ public: vector data; int offset; Compress(vector data_, int offset=0): offset(offset){ set st; for(T x: data_) st.insert(x); for(T x: st) data.push_back(x); }; int operator[](T x) { auto p = lower_bound(data.begin(), data.end(), x); assert(x == *p); return offset+(p-data.begin()); } T inv(int x){ return data[x-offset]; } int size(){ return data.size(); } }; template struct bit{ int n; vector data; bit(int n_){ n = 1; while(n < n_) n *= 2; data = vector(n+1); for(int i = 0; i <= n; i++) data[i] = 0; } T sum(int i){ T ret = 0; while(i > 0){ ret += data[i]; i -= i&-i; } return ret; } void add(int i, T x){ while(i <= n){ data[i] += x; i += i&-i; } } }; using mint = ModInt; using P = pair; int main(){ ios::sync_with_stdio(false); cin.tie(0); cout << setprecision(10) << fixed; int n; cin >> n; vector x(n), y(n); map> ys; for(int i = 0; i < n; i++) { cin >> x[i] >> y[i]; } if(x[0] > x[n-1]){ for(int i = 0; i < n; i++){ x[i] *= -1; } } if(y[0] > y[n-1]){ for(int i = 0; i < n; i++){ y[i] *= -1; } } if(y[n-1]-y[0] < x[n-1]-x[0]){ for(int i = 0; i < n; i++) swap(x[i], y[i]); } for(int i = 0; i < n; i++){ int X = x[i]+y[i]; int Y = y[i]-x[i]; x[i] = X; y[i] = Y; } for(int i = 0; i < n; i++) { ys[x[i]].push_back(y[i]); } auto cp = Compress(y, 1); int m = cp.size(); int sx = x[0], sy = y[0]; int tx = x[n-1], ty = y[n-1]; bit bt(m); map ans; for(auto [x, v]: ys){ if(x < sx) continue; if(x > tx) continue; sort(v.begin(), v.end()); for(int y: v){ if(y < sy) continue; if(y > ty) continue; if(x == sx && y == sy){ bt.add(cp[y], mint(1)); ans[P(sx, sy)] = 1; }else{ mint tmp = bt.sum(cp[y]); ans[P(x, y)] = tmp; bt.add(cp[y], tmp); } } } cout << ans[P(tx, ty)] << endl; }