#include <bits/stdc++.h>
using namespace std;
vector<int> g[20005];
int segTmin[4*20005];
int segTmax[4*20005];
int lb[4*20005];
int rb[4*20005];
vector<tuple<int,int,int> > pts;
int p[20005];
int bck[2*20005];
int fn(int x){
if(p[x] == -1) return x;
else return p[x] = fn(p[x]);
}
void un(int x,int y){
x = fn(x);
y = fn(y);
if(x != y) p[x] = y;
}
void build(int c,int l,int r){
lb[c] = l;
rb[c] = r;
if(l == r){
segTmin[c] = get<1>(pts[l]);
segTmax[c] = get<2>(pts[l]);
return;
}
int k = (l + r)/2;
build(2*c,l,k);
build(2*c+1,k+1,r);
segTmin[c] = min(segTmin[2*c],segTmin[2*c+1]);
segTmax[c] = max(segTmax[2*c],segTmax[2*c+1]);
}
int querymin(int c,int l,int r){
if(lb[c] == l && rb[c] == r) return segTmin[c];
int k = (lb[c] + rb[c])/2;
if(l <= k && k < r) return min(querymin(2*c,l,k),querymin(2*c+1,k+1,r));
else if(r <= k) return querymin(2*c,l,r);
else return querymin(2*c+1,l,r);
}
int querymax(int c,int l,int r){
if(lb[c] == l && rb[c] == r) return segTmax[c];
int k = (lb[c] + rb[c])/2;
if(l <= k && k < r) return max(querymax(2*c,l,k),querymax(2*c+1,k+1,r));
else if(r <= k) return querymax(2*c,l,r);
else return querymax(2*c+1,l,r);
}
int col[20005];
bool dfs(int u,int p = -1,int c = 1){
col[u] = c;
c = c % 2 + 1;
for(int v : g[u]){
if(v == p) continue;
if(col[v] && col[v] != c) return false;
if(col[v]) continue;
if(!dfs(v,u,c)) return false;
}
return true;
}
int main(){
memset(p,-1,sizeof(p));
int n;
scanf("%d",&n);
int a,b;
for(int i = 0; i < n; i++){
scanf("%d%d",&a,&b);
pts.emplace_back(i,a,b);
}
sort(pts.begin(),pts.end(),[](tuple<int,int,int> x,tuple<int,int,int> y){
return get<2>(x) < get<2>(y);
});
for(int i = 0; i < n; i++){
bck[get<1>(pts[i])] = get<0>(pts[i]);
}
int c = 0;
build(1,0,pts.size()-1);
for(int i = 0; i < n; i++){
int idx = upper_bound(pts.begin(),pts.end(),make_tuple(0,0,get<1>(pts[i])),[](tuple<int,int,int> x,tuple<int,int,int> y){
return get<2>(x) < get<2>(y);
}) - pts.begin();
if(idx <= i-1 && querymin(1,idx,i-1) < get<1>(pts[i])){
int l = querymin(1,idx,i-1);
un(bck[l],get<0>(pts[i]));
g[bck[l]].push_back(get<0>(pts[i]));
g[get<0>(pts[i])].push_back(bck[l]);
}
}
sort(pts.begin(),pts.end(),[](tuple<int,int,int> x,tuple<int,int,int> y){
return get<1>(x) < get<1>(y);
});
for(int i = 0; i < n; i++){
bck[get<2>(pts[i])] = get<0>(pts[i]);
}
build(1,0,pts.size()-1);
for(int i = n-1; i >= 0; i--){
int idx = lower_bound(pts.begin(),pts.end(),make_tuple(0,get<2>(pts[i]),0),[](tuple<int,int,int> x,tuple<int,int,int> y){
return get<1>(x) < get<1>(y);
}) - pts.begin() - 1;
if(idx >= i+1 && querymax(1,i+1,idx) > get<2>(pts[i])){
int r = querymax(1,i+1,idx);
un(bck[r],get<0>(pts[i]));
g[bck[r]].push_back(get<0>(pts[i]));
g[get<0>(pts[i])].push_back(bck[r]);
}
}
for(int i = 0; i < pts.size(); i++){
if(col[i]) continue;
if(!dfs(i)){
printf("0\n");
return 0;
}
}
set<int> s;
for(int i = 0; i < n; i++){
s.insert(fn(i));
}
c = s.size();
int ans = 1;
for(int i = 0; i < c; i++){
ans *= 2;
ans %= 1000000007;
}
printf("%d\n",ans);
return 0;
}
