#include <cstdio>
#include <iostream>
#include <algorithm>
#include <set>
#include <cstdlib>
#define fi first
#define se second
using namespace std;
typedef pair<int,int> pii;
const int N=1000010,P=1e9+7;
inline char nc(){
static char buf[100000],*p1=buf,*p2=buf;
return p1==p2&&(p2=(p1=buf)+fread(buf,1,100000,stdin),p1==p2)?EOF:*p1++;
}
inline void read(int &x){
char c=nc(); x=0;
for(;c>'9'||c<'0';c=nc());for(;c>='0'&&c<='9';x=x*10+c-'0',c=nc());
}
int n,cnt,a[N],b[N],id[N],G[N],t;
set<pii> S;
pii q[N];
struct edge{
int t,nx;
}E[N<<2];
inline bool cmp(const int &x,const int &y){
return a[x]<a[y];
}
inline void addedge(int x,int y){
E[++cnt].t=y; E[cnt].nx=G[x]; G[x]=cnt;
E[++cnt].t=x; E[cnt].nx=G[y]; G[y]=cnt;
}
int cl[N];
void dfs(int x,int c){
if(cl[x]){
if(cl[x]!=c) puts("0"),exit(0);
return ;
}
cl[x]=c;
for(int i=G[x];i;i=E[i].nx) dfs(E[i].t,c^1);
}
int nxt[N];
int main(){
read(n);
for(int i=1;i<=n;i++)
read(a[i]),read(b[i]),id[i]=i;
sort(id+1,id+1+n,cmp);
for(int i=1;i<=n;i++){
while(!S.empty() && S.begin()->fi<a[id[i]]){
int cur=S.begin()->se;
S.erase(S.begin());
if(nxt[cur]) S.insert(pii(b[nxt[cur]],nxt[cur]));
}
set<pii>::iterator cur=S.insert(pii(b[id[i]],id[i])).fi;
t=0;
while(cur!=S.begin()){
cur--; q[++t]=*cur;
}
int mx=1<<29;
for(int j=1;j<=t;j++){
mx=min(mx,q[j].fi);
addedge(q[j].se,id[i]);
}
for(int i=1;i<t;i++) S.erase(q[i]);
for(int i=2;i<=t;i++) nxt[q[i].se]=q[i-1].se;
}
int ans=1;
for(int i=1;i<=n;i++)
if(!cl[i]){
dfs(i,2); ans=2*ans%P;
}
printf("%d\n",ans);
return 0;
}
