#include <bits/stdc++.h>

#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/detail/standard_policies.hpp>
using namespace __gnu_pbds;

#if !ONLINE_JUDGE
#define debug
#endif

using namespace std;
 
/*******  All Required define Pre-Processors and typedef Constants *******/
#define mem(a, b) memset(a, (b), sizeof(a))
#define repd(i,k) for(int i=k;i>=0;i--)
#define rep(i,k) for(int i=0;i<k;i++)
#define repn(i,k1,k2) for(ll i=k1;i<k2;i++)
#define sz(x) (ll)(x).size()
#define ff first
#define ss second

#define all(cont) cont.begin(), cont.end()
#define rall(cont) cont.end(), cont.begin()
#define mp make_pair
#define pb push_back
#define eb emplace_back
#define INF (int)1e9
#define EPS 1e-9
#define PI 3.1415926535897932384626433832795
#define MOD 1000000007
#define ee6 (ll)1000001
#define ee5 (ll)100001

#define trav(a, v) for(auto& a : v)

#define tt ll t;cin>>t; while(t--)
typedef long long int ll;
 
typedef pair<ll, ll> pr;
typedef vector<ll> vi;
typedef vector<string> vs;
typedef vector<pr> vpr;
typedef vector<vpr>vvpr;
typedef vector<vi> vvi;

//*X.find_by_order(2) element at index=2
//X.order_of_key(1) how many elements strictly less than 1

template <typename T>
using ordered_set = tree<T, null_type, less<T>, rb_tree_tag,
    tree_order_statistics_node_update>;

#ifdef debug
#define dbg(...) { cerr<<"[ "; dump(#__VA_ARGS__, __VA_ARGS__);}
#undef endl
template <typename Arg1,typename Arg2>
ostream& operator << (ostream& out, const pair<Arg1,Arg2> &x) {
    return out<<"("<<x.ff<<","<<x.ss<<")";
}
 
template <typename Arg1>
ostream& operator << (ostream& out, const vector<Arg1> &a) {
    out<<"[";for(const auto &x:a)out<<x<<",";return out<<"]";
}
 
template <typename Arg1>
ostream& operator << (ostream& out, const set<Arg1> &a) {
    out<<"[";for(const auto &x:a)out<<x<<",";return out<<"]";
}
 
template <typename Arg1,typename Arg2>
ostream& operator << (ostream& out, const map<Arg1,Arg2> &a) {
    out<<"[";for(const auto &x:a)out<<x<<",";return out<<"]";
}
 
template <typename Arg1,typename Arg2>
ostream& operator << (ostream& out, const unordered_map<Arg1,Arg2> &a) {
    out<<"[";for(const auto &x:a)out<<x<<",";return out<<"]";
} 
 
template <typename Arg1>
void dump(const string name, Arg1&& arg1){
    cerr << name << " : " << arg1 << " ] " << endl;
}
 
template <typename Arg1, typename... Args>
void dump(const string names, Arg1&& arg1, Args&&... args){
    const string name = names.substr(0,names.find(','));
    cerr<<name<<" : "<<arg1<<" | ";
    dump(names.substr(1+(int)name.size()), args...);
}
#else
    #define dbg(args...)
#endif
 
ll powmod(ll x, ll y) 
{ 
    ll res = 1;  
    x = x % MOD;
    while (y > 0) 
    { 
        if (y & 1) 
          res = (res*x) % MOD; 
        y = y>>1; // y = y/2 
        x = (x*x) % MOD;   
    } 
    return res; 
} 
const ll N=ee6;
ll fact[N],inv[N],invfact[N];
void pre2()
{
  fact[0]=1;
  for(ll i=1;i<N;i++)
    fact[i]=(fact[i-1]*i)%MOD;
  //calculate inverses of [1,N] mod p
  inv[1]=1;
  for(ll i=2;i<N;i++)inv[i]=inv[MOD%i]*(MOD-MOD/i)%MOD;

  invfact[0]=1;
  for(ll i=1;i<N;i++)invfact[i]=(invfact[i-1]*inv[i])%MOD;
}
 
ll ncr(ll n,ll r)
{
  if(r>n)return 0;
  if(n==r)return 1;
  if(n<0 or r<0)return 0;
  return fact[n]*invfact[r]%MOD*invfact[n-r]%MOD;
}

vector<ll>colors;
ll mark[2*ee5];
vector<ll>wt[2*ee5];
int main()
{
  #if !ONLINE_JUDGE
  //freopen("in.txt","r",stdin);
  #endif
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  pre2();
  ll n,x,y;cin>>n>>x>>y;
  rep(i,n){
    ll c,w;cin>>c>>w;
    wt[c].eb(w);
    colors.pb(c);
  }  

  sort(all(colors));
  colors.erase(unique(all(colors)),colors.end());

  ll fmin=-1,smin=-1;
  for(auto c:colors){
    sort(all(wt[c]));    
    mark[c]=upper_bound(all(wt[c]),x-wt[c][0])-wt[c].begin()-1;

    if(fmin==-1)fmin=c,smin=c;
    else if(wt[c][0]<=wt[fmin][0]){
      smin=fmin;
      fmin=c;
    }
    else if(wt[c][0]<wt[smin][0]){
      smin=c;
    }
  }

  for(auto c:colors){
    if(c==fmin)continue;
    ll x=(ll)(upper_bound(all(wt[c]),y-wt[fmin][0])-wt[c].begin())-1;
    if(x>=0)mark[c]=max(mark[c],x);
    else mark[c]=-1;
  }

  ll tmp=(ll)(upper_bound(all(wt[fmin]),y-wt[smin][0])-wt[fmin].begin())-1;
  if(tmp>=0)mark[fmin]=max(mark[fmin],tmp);
  else mark[fmin] =-1;

//  for(auto e:colors)cout<<mark[e]<<" ";

  ll num=0;ll deno=1;
  for(auto c:colors){
    num=num+mark[c]+1;
    deno=(deno*invfact[mark[c]+1])%MOD;
  }
  cout<<fact[num]*deno%MOD;
} 

Measured memory_bytes: 36080