// #define DEBUGGING
#include <bits/stdc++.h>
#define endl '\n'
#define ALL(v) std::begin(v), std::end(v)
#define ALLR(v) std::rbegin(v), std::rend(v)
using ll = std::int64_t;
using ull = std::uint64_t;
using pll = std::pair<ll, ll>;
using tll = std::tuple<ll, ll, ll>;
template <typename T> using vec = std::vector<T>;
template <typename T> using vvec = vec<vec<T>>;
template <typename T> const T& var_min(const T &t) { return t; }
template <typename T> const T& var_max(const T &t) { return t; }
template <typename T, typename... Tail> const T& var_min(const T &t, const Tail&... tail) { return std::min(t, var_min(tail...)); }
template <typename T, typename... Tail> const T& var_max(const T &t, const Tail&... tail) { return std::max(t, var_max(tail...)); }
template <typename T, typename... Tail> void chmin(T &t, const Tail&... tail) { t = var_min(t, tail...); }
template <typename T, typename... Tail> void chmax(T &t, const Tail&... tail) { t = var_max(t, tail...); }
template <typename T> const T& clamp(const T &t, const T &low, const T &high) { return std::max(low, std::min(high, t)); }
template <typename T> void chclamp(T &t, const T &low, const T &high) { return t = clamp(t, low, high); }
namespace init__ { struct InitIO { InitIO() { std::cin.tie(nullptr); std::ios_base::sync_with_stdio(false); std::cout << std::fixed << std::setprecision(30); } } init_io; }
#define mv_rec make_v(init, tail...)
template <typename T> T make_v(T init) { return init; }
template <typename T, typename... Tail> auto make_v(T init, size_t s, Tail... tail) { return vec<decltype(mv_rec)>(s, mv_rec); }
#undef mv_rec

#ifdef DEBUGGING
#else
#define DEBUG(...) 0
#define DEBUG_SEPARATOR_LINE 0
#endif

namespace math {

template <typename T>
constexpr T pow(const T &n, ll k) {
    T ret = T::mul_id_ele();
    T cur = n;
    while (k) {
        if (k & 1) ret *= cur;
        cur *= cur;
        k /= 2;
    }
    return ret;
}

}

namespace math {

template <ll Mod>
struct Modint {

    constexpr Modint(ll x) : x(x) { }
    
    constexpr Modint() : Modint(0) { }
    
    constexpr static Modint<Mod> add_id_ele() { 
        return Modint<Mod>(0); 
    }
    
    constexpr static Modint<Mod> mul_id_ele() { 
        return Modint<Mod>(1); 
    }
    
    constexpr ll& value() { 
        return x; 
    }
    
    constexpr ll value() const {
        return x; 
    }

    constexpr Modint& operator +=(const Modint &oth) {
        x += oth.value();
        if (Mod < x) x -= Mod;
        return *this;
    }

    constexpr Modint& operator -=(const Modint &oth) {
        x += Mod - oth.value();
        if (Mod < x) x -= Mod;
        return *this;
    }

    constexpr Modint& operator *=(const Modint &oth) {
        x *= oth.value();
        x %= Mod;
        return *this;
    }

    constexpr Modint& operator /=(const Modint &oth) {
        (*this) *= oth.inv();
        return *this;
    }

    constexpr Modint operator +(const Modint &oth) const {
        return Modint(x) += oth;
    }

    constexpr Modint operator -(const Modint &oth) const {
        return Modint(x) -= oth;
    }

    constexpr Modint operator *(const Modint &oth) const {
        return Modint(x) *= oth;
    }

    constexpr Modint operator /(const Modint &oth) const {
        return Modint(x) /= oth;
    }

    constexpr Modint operator -() const {
        return Modint((x != 0) * (Mod - x)); 
    }

    template <typename T>
    constexpr typename std::enable_if<std::is_integral<T>::value, const Modint&>::type
    operator =(T t) { (*this) = Modint(t); return *this; }

    constexpr Modint inv() const {
        return ::math::pow(*this, Mod - 2);
    }

    constexpr ll mod() const {
        return Mod;
    }

private:
    ll x;
};

}

namespace math {

template <ll Mod>
class Combination {
    using mint = Modint<Mod>;

    ssize_t maxv;
    vec<mint> factv, ifactv;

public:
    Combination(ssize_t maxv) : maxv(maxv), factv(maxv + 1), ifactv(maxv + 1) {
        factv[0] = mint(1);
        for (ll i = 1; i <= maxv; i++) factv[i] = factv[i - 1] * i;
        ifactv.back() = factv.back().inv();
        for (ll i = maxv - 1; 0 <= i; i--) ifactv[i] = ifactv[i + 1] * (i + 1);
    }

    mint fact(ll n) const { return factv[n]; }

    mint ifact(ll n) const { return ifactv[n]; }

    mint perm(ll n, ll k) const { return factv[n] * ifactv[n - k]; }

    mint comb(ll n, ll k) const { return perm(n, k) * ifactv[k]; }
};

}

namespace tree {

struct UnionFind {
    vec<ll> rank, par;
    vec<ssize_t> sz;

    UnionFind(ll n) : rank(n, 1), par(n), sz(n, 1) {
        iota(ALL(par), 0);
    }

    ll find(ll n) {
        return (n == par[n] ? n : par[n] = find(par[n]));
    }

    bool unit(ll x, ll y) {
        ll px = find(x), py = find(y);
        if (px == py) return false;
        if (rank[px] < rank[py]) std::swap(px, py);
        par[py] = px;
        rank[px] += (rank[px] == rank[py]);
        sz[px] += sz[py];
        return true;
    }

    bool same(ll x, ll y) {
        return find(x) == find(y);
    }

    ssize_t size(ll n) {
        return sz[find(n)];
    }
};

}

constexpr ll mod = 1e9 + 7;
const ll inf = 5e15;
math::Combination<mod> comb(1e6);
using mint = math::Modint<mod>;

using namespace std;
int main() {
    ll n, x, y;
    cin >> n >> x >> y;
    vec<pll> cw(n);
    for (auto &&e : cw) {
        ll c, w;
        cin >> c >> w;
        e = pll(c - 1, w);
    }

    pll init(inf, inf);
    vec<pll> minw(n, init);
    for (ll i = 0; i < n; i++) {
        ll c, w;
        tie(c, w) = cw[i];
        auto cand = pll(w, i);
        chmin(minw[c], cand);
    }

    vec<tll> wic;
    for (ll c = 0; c < n; c++) {
        if (minw[c] == init) continue;
        ll w, i;
        tie(w, i) = minw[c];
        wic.emplace_back(w, i, c);
    }
    sort(ALL(wic));

    tree::UnionFind uf(n);
    for (ll i = 0; i < n; i++) {
        {
            ll c, w;
            tie(c, w) = cw[i];
            if (minw[c].second != i) {
                ll sum = minw[c].first + w;
                if (sum <= x) uf.unit(i, minw[c].second);
            }
        }
        {
            ll j = 0;
            do {
                if (cw[i].first == get<2>(wic[0])) j++;
                if (wic.size() <= j) break;
                ll w, idx, c;
                tie(w, idx, c) = wic[j];
                ll sum = cw[i].second + w;
                if (sum <= y) uf.unit(idx, i);
            } while (false);
        }
    }

    map<ll, vec<ll>> groups;
    for (ll i = 0; i < n; i++) groups[uf.find(i)].push_back(i);
    mint ans = 1;
    for (auto &&e : groups) {
        DEBUG(e);
        map<ll, ll> cols;
        for (ll idx : e.second) cols[cw[idx].first]++;
        ans *= comb.fact(e.second.size());
        DEBUG(cols);
        for (auto &&d : cols) ans *= comb.ifact(d.second);
    }
    cout << ans.value() << endl;
    return 0;
}


Measured memory_bytes: 51056