// Original C++ solution (slower):
#include<iostream>

#include<cstdio>

#include<cstdlib>

#include<cmath>

#include<cstring>

#include<algorithm>

#include<vector>

#define ll long long

#define re register

#define il inline

#define pb push_back

#define fp(i,a,b) for(re int i=a;i<=b;++i)

#define fq(i,a,b) for(re int i=a;i>=b;--i)

using namespace std;

const int N=2e5+100,mod=1e9+7;

int n,x,X,Y,mn[N],mn1=mod,mn2=mod,ans=1,inv[N],tot;

vector<int>V[N];

il ll gi()

{

  re ll x=0,t=1;

  re char ch=getchar();

  while(ch!='-'&&(ch<'0'||ch>'9')) x=x*10+ch-48,ch=getchar();

  if(ch=='-') t=-1,ch=getchar();

  while(ch>='0'&&ch<='9') x=x*10+ch-48,ch=getchar();

  return x*t;

}

int main()

{

  n=gi();X=gi();Y=gi();

  inv[0]=inv[1]=1;

  fp(i,1,n) x=gi(),V[x].pb(gi());

  fp(i,2,n) inv[i]=1ll*(mod-mod/i)*inv[mod%i]%mod;

  fp(i,2,n) inv[i]=1ll*inv[i]*inv[i-1]%mod;

  fp(i,1,n)

    if(V[i].size())

      {

	sort(V[i].begin(),V[i].end());

        mn2=min(mn2,mn[i]=V[i][0]);

	if(mn2<mn1) swap(mn1,mn2);

      }

    else mn[i]=mod;

  fp(i,1,n)

    {

      re int mm=(mn[i]==mn1?mn2:mn1),sz=V[i].size();

      while(sz>1&&V[i][sz-1]+mm>Y&&V[i][sz-1]+mn[i]>X) --sz;

      if(mm+mn[i]<=Y) ans=1ll*ans*inv[sz]%mod,tot+=sz;

    }

  fp(i,1,tot) ans=1ll*ans*i%mod;

  printf("%d\n",ans);

  return 0;

}


// Optimized solution to the same problem (faster):
#include<cstdio>

#define ll long long

#define mod 1000000007ll

struct Edge{

    int to,nex;

}edge[3000010];

int c[200010],head[200010],pos[200010],cnt[200010],tot;

ll w[200010],fac[200010],rfac[200010],min[200010];

bool v[200010];

ll pow(ll a,ll b){

    ll ans=1,base=a;

    while(b){

        if(b&1)ans=(ans*base)%mod;

        base=(base*base)%mod;

        b>>=1;

    }

    return ans;

}

ll C(ll n,ll k){

    return(((fac[n]*rfac[n-k])%mod)*rfac[k])%mod;

}

void add(int a,int b){

    tot++;

    edge[tot].to=b;

    edge[tot].nex=head[a];

    head[a]=tot;

}

void dfs(int x){

    v[x]=1;

    for(int i=head[x];i;i=edge[i].nex){

        if(!v[edge[i].to])dfs(edge[i].to);

    }

}

int main(){

    int n,i,fir,sec=0;

    ll X,Y,min1,min2,tot,ans;

    scanf("%d%lld%lld",&n,&X,&Y);

    fac[0]=1;

    for(i=1;i<=n;i++){

        scanf("%d%lld",c+i,w+i);

        fac[i]=(i*fac[i-1])%mod;

        min[i]=2147483647;

    }

    rfac[n]=pow(fac[n],mod-2);

    for(i=n;i>0;i--)rfac[i-1]=(i*rfac[i])%mod;

    for(i=1;i<=n;i++){

        if(w[i]<min[c[i]]){

            min[c[i]]=w[i];

            pos[c[i]]=i;

        }

    }

    for(i=1;i<=n;i++){

        if(i!=pos[c[i]]&&w[i]+min[c[i]]<=X){

            add(i,pos[c[i]]);

            add(pos[c[i]],i);

        }

    }

    min1=min2=2147483647;

    for(i=1;i<=n;i++){

        if(w[i]<min1){

            min1=w[i];

            fir=i;

        }

    }

    for(i=1;i<=n;i++){

        if(w[i]<=min2&&c[i]!=c[fir]){

            min2=w[i];

            sec=i;

        }

    }

    for(i=1;i<=n;i++){

        if(i==fir)continue;

        if(c[i]!=c[fir]&&w[i]+w[fir]<=Y){

            add(i,fir);

            add(fir,i);

        }

        if(sec&&c[i]!=c[sec]&&w[i]+w[sec]<=Y){

            add(i,sec);

            add(sec,i);

        }

    }

    dfs(fir);

    tot=0;

    for(i=1;i<=n;i++){

        if(v[i]){

            tot++;

            cnt[c[i]]++;

        }

    }

    ans=1;

    for(i=1;i<=n;i++){

        if(cnt[i]){

            ans=(ans*C(tot,cnt[i]))%mod;

            tot-=cnt[i];

        }

    }

    printf("%lld",ans);

}

// Fastest known solution for this problem: