#include <bits/stdc++.h>
#define ll long long
#define INF 1000000005
#define MOD 1000000007
#define EPS 1e-10
#define rep(i,n) for(int i=0;i<(int)(n);++i)
#define rrep(i,n) for(int i=(int)(n)-1;i>=0;--i)
#define srep(i,s,t) for(int i=(int)(s);i<(int)(t);++i)
#define each(a,b) for(auto& (a): (b))
#define all(v) (v).begin(),(v).end()
#define len(v) (int)(v).size()
#define zip(v) sort(all(v)),v.erase(unique(all(v)),v.end())
#define cmx(x,y) x=max(x,y)
#define cmn(x,y) x=min(x,y)
#define fi first
#define se second
#define pb push_back
#define show(x) cout<<#x<<" = "<<(x)<<endl
#define spair(p) cout<<#p<<": "<<p.fi<<" "<<p.se<<endl
#define sar(a,n) cout<<#a<<":";rep(pachico,n)cout<<" "<<a[pachico];cout<<endl
#define svec(v) cout<<#v<<":";rep(pachico,v.size())cout<<" "<<v[pachico];cout<<endl
#define svecp(v) cout<<#v<<":";each(pachico,v)cout<<" {"<<pachico.first<<":"<<pachico.second<<"}";cout<<endl
#define sset(s) cout<<#s<<":";each(pachico,s)cout<<" "<<pachico;cout<<endl
#define smap(m) cout<<#m<<":";each(pachico,m)cout<<" {"<<pachico.first<<":"<<pachico.second<<"}";cout<<endl

using namespace std;

typedef pair<int,int> P;
typedef pair<ll,ll> pll;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<ll> vl;
typedef vector<vl> vvl;
typedef vector<double> vd;
typedef vector<P> vp;
typedef vector<string> vs;

const int MAX_N = 200005;

ll inv[MAX_N],fac[MAX_N],finv[MAX_N];

void make()
{
	fac[0] = fac[1] = 1;
	finv[0] = finv[1] = 1;
	inv[1] = 1;
	for(int i=2;i<MAX_N;i++){
		inv[i] = MOD - inv[MOD%i] * (MOD/i) % MOD;
		fac[i] = fac[i-1] * (ll) i % MOD;
		finv[i] = finv[i-1] * inv[i] % MOD;
	}
}

ll add(ll x,ll y)
{
    return (x + y)%MOD;
}

ll sub(ll x,ll y)
{
    return (x+MOD-y)%MOD;
}

ll mul(ll x,ll y)
{
    return x*y%MOD;
}

class UF {
private:
    int sz;
public:
    vector<int> kind;   //所属しているグループ番号
    vector<vector<int> > inc;   //グループのメンバー
    UF(){}
    UF(int node_size){ sz = node_size; kind.resize(sz),inc.resize(sz); rep(i,sz){ kind[i] = i; inc[i].pb(i); } }
    bool same(int a,int b){ return kind[a] == kind[b]; }
    void unite(int a,int b)
    { if(same(a,b)) return; if(inc[kind[a]].size() < inc[kind[b]].size()) swap(a,b);
        int ga = kind[a],gb = kind[b]; rep(i,inc[gb].size()) kind[inc[gb][i]] = ga;
        inc[ga].insert(inc[ga].end(),inc[gb].begin(),inc[gb].end()); inc[gb].clear(); }
};

vector<int> vec[MAX_N];
multiset<int> st;

int main()
{
    cin.tie(0);
    ios::sync_with_stdio(false);
    int n,x,y;
    cin >> n >> x >> y;
    vi c(n),w(n);
    rep(i,n){
        cin >> c[i] >> w[i];
        --c[i];
        st.insert(w[i]);
        vec[c[i]].pb(w[i]);
    }
    make();
    // UF uf(n);
    map<int,int> mp;
    int cnt = 0;
    rep(i,n){
        if(len(vec[i])){
            sort(all(vec[i]));
            rep(j,len(vec[i])){
                st.erase(st.find(vec[i][j]));
            }
            if(len(st) && *st.begin() + vec[i][0] <= y){
                int dame = upper_bound(all(vec[i]),max(x-vec[i][0],y-*st.begin())) - vec[i].begin();
                if(dame == 0){
                    dame++;
                }
                cnt += dame;
                mp[i] = dame;
            }
            rep(j,len(vec[i])){
                st.insert(vec[i][j]);
            }
        }
    }
    ll ans = fac[cnt];
    each(it,mp){
        ans = mul(ans,finv[it.se]);
    }
    cout << ans << "\n";
    return 0;
}


Measured memory_bytes: 30592