#include <iostream>
#include <string>
#include <cmath>
#include<algorithm>
#include<stack>
#include<queue>
#include<map>
#include<set>
#include<iomanip>
#define _USE_MATH_DEFINES
#include <math.h>
#include <functional>
#include<complex>
using namespace std;

#define rep(i,x) for(ll i=0;i<x;i++)
#define repn(i,x) for(ll i=1;i<=x;i++)

typedef long long ll;
const ll INF = 1e17;
const ll MOD = 1000000007;
const ll MAX = 4000001;
const double eps = 1E-18;

ll max(ll a, ll b) {
	if (a > b) { return a; }
	return b;
}

ll min(ll a, ll b) {
	if (a > b) { return b; }
	return a;
}

ll gcd(ll a, ll b) {
	if (b == 0) { return a; }
	if (a < b) { return gcd(b, a); }
	return gcd(b, a % b);
}

ll lcm(ll a, ll b) {
	return a / gcd(a, b) * b;
}

struct edge {
	ll ind;
	ll fr;
	ll to;
	ll d;
};

class mint {
	long long x;
public:
	mint(long long x = 0) : x((x% MOD + MOD) % MOD) {}
	mint operator-() const {
		return mint(-x);
	}
	mint& operator+=(const mint& a) {
		if ((x += a.x) >= MOD) x -= MOD;
		return *this;
	}
	mint& operator-=(const mint& a) {
		if ((x += MOD - a.x) >= MOD) x -= MOD;
		return *this;
	}
	mint& operator*=(const  mint& a) {
		(x *= a.x) %= MOD;
		return *this;
	}
	mint operator+(const mint& a) const {
		mint res(*this);
		return res += a;
	}
	mint operator-(const mint& a) const {
		mint res(*this);
		return res -= a;
	}
	mint operator*(const mint& a) const {
		mint res(*this);
		return res *= a;
	}

	mint pow(ll t) const {
		if (!t) return 1;
		mint a = pow(t >> 1);
		a *= a;
		if (t & 1) a *= *this;
		return a;
	}

	mint operator^(const ll& t)const {
		if (!t) return 1;
		mint a = *this^(t >> 1);
		a *= a;
		if (t & 1) a *= *this;
		return a;
	}

	// for prime MOD
	mint inv() const {
		return pow(MOD - 2);
	}
	mint& operator/=(const mint& a) {
		return (*this) *= a.inv();
	}
	mint operator/(const mint& a) const {
		mint res(*this);
		return res /= a;
	}

	friend ostream& operator<<(ostream& os, const mint& m) {
		os << m.x;
		return os;
	}
};

///////////////////////////

vector<mint> frac, ifrac;
void finit(ll X) {
	frac.assign(X + 1, 1);
	ifrac.assign(X + 1, 1);

	repn(i, X) {
		frac[i] = frac[i - 1] * i;
		ifrac[i] = ifrac[i - 1] / i;
	}

}

mint com(ll n, ll m) {
	if (n < 0 || m < 0 || n < m) { return 0; }
	return frac[n] * ifrac[m] * ifrac[n - m];
}


int main() {
	ll N, X, Y;
	cin >> N >> X >> Y;
	vector<vector<ll>> ball(N + 1);

	repn(i, N) {
		ll c, w;
		cin >> c >> w;
		ball[c].push_back(w);
	}

	vector<pair<ll, pair<ll,ll>>> grp;

	vector<pair<ll, ll>> mincol;

	repn(c, N) {
		if (ball[c].size() == 0) { continue; }

		sort(ball[c].begin(), ball[c].end());

		ll ini = ball[c][0];
		ll t = ball[c].size();
		repn(i, ball[c].size()-1) {
			if (ball[c][i] + ini > X) { t = i; break; }
		}

		//cout << c << t << endl << flush;

		grp.push_back({ ini,{t,c} });

		mincol.push_back({ ini,c });

		for (ll i = t; i < ball[c].size(); i++) {
			grp.push_back({ ball[c][i],{1,c} });
		}
	}

	sort(grp.begin(), grp.end());
	sort(mincol.begin(), mincol.end());

	ll C = mincol[0].second;

	vector<ll> frb(N + 1, 0);
	rep(i,grp.size()) {
		if (grp[i].first + mincol[0].first > Y) { continue; }
		if (grp[i].second.second == mincol[0].second && mincol.size()>0&&grp[i].first + mincol[1].first > Y) { continue; }
		frb[grp[i].second.second] += grp[i].second.first;
	}
	//repn(i, N) cout << frb[i] << endl;

	ll sum = 0;
	repn(i, N) sum += frb[i];

	finit(N + 1);

	mint ans = 1;

	repn(i, N) {
		ans *= com(sum, frb[i]);
		sum -= frb[i];
	}

	cout << ans << endl;


}


Measured memory_bytes: 23068