#include <bits/stdc++.h>
#define rep(i,n) for(int i=0;i<(int)(n);i++)
#define rep1(i,n) for(int i=1;i<=(int)(n);i++)
#define all(c) c.begin(),c.end()
#define pb push_back
#define fs first
#define sc second
#define show(x) cout << #x << " = " << x << endl
#define chmin(x,y) x=min(x,y)
#define chmax(x,y) x=max(x,y)
using namespace std;
template<class S,class T> ostream& operator<<(ostream& o,const pair<S,T> &p){return o<<"("<<p.fs<<","<<p.sc<<")";}
template<class T> ostream& operator<<(ostream& o,const vector<T> &vc){o<<"sz = "<<vc.size()<<endl<<"[";for(const T& v:vc) o<<v<<",";o<<"]";return o;}
template<unsigned int mod_>
struct ModInt{
	using uint = unsigned int;
	using ll = long long;
	using ull = unsigned long long;

	constexpr static uint mod = mod_;

	uint v;
	ModInt():v(0){}
	ModInt(ll v):v(normS(v%mod+mod)){}
	explicit operator bool() const {return v!=0;}
	static uint normS(const uint &x){return (x<mod)?x:x-mod;}		// [0 , 2*mod-1] -> [0 , mod-1]
	static ModInt make(const uint &x){ModInt m; m.v=x; return m;}
	ModInt operator+(const ModInt& b) const { return make(normS(v+b.v));}
	ModInt operator-(const ModInt& b) const { return make(normS(v+mod-b.v));}
	ModInt operator-() const { return make(normS(mod-v)); }
	ModInt operator*(const ModInt& b) const { return make((ull)v*b.v%mod);}
	ModInt operator/(const ModInt& b) const { return *this*b.inv();}
	ModInt& operator+=(const ModInt& b){ return *this=*this+b;}
	ModInt& operator-=(const ModInt& b){ return *this=*this-b;}
	ModInt& operator*=(const ModInt& b){ return *this=*this*b;}
	ModInt& operator/=(const ModInt& b){ return *this=*this/b;}
	ll extgcd(ll a,ll b,ll &x,ll &y) const{
		ll u[]={a,1,0},v[]={b,0,1};
		while(*v){
			ll t=*u/ *v;
			rep(i,3) swap(u[i]-=t*v[i],v[i]);
		}
		if(u[0]<0) rep(i,3) u[i]=-u[i];
		x=u[1],y=u[2];
		return u[0];
	}
	ModInt inv() const{
		ll x,y;
		extgcd(v,mod,x,y);
		return make(normS(x+mod));
	}
	bool operator==(const ModInt& b) const { return v==b.v;}
	bool operator!=(const ModInt& b) const { return v!=b.v;}
	friend istream& operator>>(istream &o,ModInt& x){
		ll tmp;
		o>>tmp;
		x=ModInt(tmp);
		return o;
	}
	friend ostream& operator<<(ostream &o,const ModInt& x){ return o<<x.v;}
};
using mint = ModInt<1000000007>;

const int MN=200000;
typedef long long ll;
int N;
ll X,Y;
ll inf=1e10;
vector<ll> c2ws[MN];
int can[MN];
bool cancol[MN];
mint f[MN+1];
int main(){
	f[0]=1;
	rep1(i,MN) f[i]=f[i-1]*i;
	cin>>N>>X>>Y;
	vector<int> cs;
	rep(i,N){
		int c,w;
		cin>>c>>w;
		c--;
		cs.pb(c);
		c2ws[c].pb(w);
	}
	sort(all(cs));
	cs.erase(unique(cs.begin(),cs.end()),cs.end());
	int C=cs.size();
	if(C==1){
		puts("1");
		return 0;
	}
	rep(i,C) c2ws[i]=c2ws[cs[i]];
	rep(i,C) sort(all(c2ws[i]));
	ll mn=inf,mn2=inf;
	int ag=-1,ag2=-1;
	rep(i,C){
		ll w = c2ws[i].front();
		if(mn>w){
			mn2=mn,ag2=ag;
			mn=w,ag=i;
		}else if(mn2>w){
			mn2=w,ag2=i;
		}
	}
	rep(i,C){
		int amin=c2ws[i].front();
		int bmin=(ag==i?mn2:mn);
		ll lim=max(X-amin,Y-bmin);
		int id = upper_bound(all(c2ws[i]),lim)-c2ws[i].begin();
		can[i]=id;
	}
	mint ans=1;
	int sum=0;
	rep(i,C){
		if(ag==i || mn+c2ws[i].front()<=Y){
			cancol[i]=1;
			ans/=f[can[i]];
			sum+=can[i];
		}
	}
	ans*=f[sum];
	cout<<ans<<endl;
}


Measured memory_bytes: 12916