#include "bits/stdc++.h"
using namespace std;
#define ar array
const int N = 2e6 + 5;
const int mod = 1e9 + 7;
struct ST{
ar<int, 2> tree[N << 2];
void sett(int i, int v, int lx = 0, int rx = N, int x = 1){
if(lx == rx) { tree[x] = {v, v}; return; }
int m = (lx + rx) >> 1;
if(i <= m) sett(i, v, lx, m, x<<1);
else sett(i, v, m+1, rx, x<<1|1);
tree[x][0] = min(tree[x<<1][0], tree[x<<1|1][0]);
tree[x][1] = max(tree[x<<1][1], tree[x<<1|1][1]);
}
ar<int, 2> get(int l, int r, int lx = 0, int rx = N, int x = 1){
if(lx > r || rx < l) return {N, -N};
if(lx >= l && rx <= r) return tree[x];
int m = (lx + rx) >> 1;
auto L = get(l, r, lx, m, x<<1);
auto R = get(l, r, m+1, rx, x<<1|1);
return {min(L[0], R[0]), max(L[1], R[1])};
}
}tree;
vector<int> edges[N], sub[N];
int l[N], r[N], id[N], used[N];
int c[N], par[N];
signed main(){
ios::sync_with_stdio(0); cin.tie(0);
int n; cin>>n;
vector<int> cmp;
for(int i=0;i<n;i++){
cin>>l[i]>>r[i];
tree.sett(l[i], r[i]);
tree.sett(r[i], l[i]);
id[l[i]] = id[r[i]] = i;
par[i] = i, cmp.push_back(i);
sub[i].push_back(i);
}
while(true){
vector<ar<int, 2>> merge;
for(auto i : cmp){
for(auto x : sub[i]){
tree.sett(l[x], l[x]);
tree.sett(r[x], r[x]);
}
for(auto x : sub[i]){
auto m = tree.get(l[x], r[x]);
if(m[0] < l[x]){
merge.push_back({x, id[m[0]]});
break;
} if(r[x] < m[1]){
merge.push_back({x, id[m[1]]});
break;
}
}
for(auto x : sub[i]){
tree.sett(l[x], r[x]);
tree.sett(r[x], l[x]);
}
}
for(auto x : merge){
int a = par[x[0]], b = par[x[1]];
if(a == b) continue;
edges[x[0]].push_back(x[1]);
edges[x[1]].push_back(x[0]);
if(sub[a].size() < sub[b].size()) swap(a, b);
for(auto x : sub[b]) par[x] = a, sub[a].push_back(x);
sub[b].clear();
}
int last = cmp.size();
cmp.clear();
for(int i=0;i<n;i++){
if(i == par[i]) cmp.push_back(i);
}
if((int)cmp.size() == last) break;
}
for(int i=0;i<n;i++) tree.sett(l[i], l[i]), tree.sett(r[i], r[i]);
vector<int> tt[2];
function<void(int)> dfs = [&](int u){
used[u] = 1;
tt[c[u]].push_back(u);
for(auto x : edges[u]){
if(!used[x]){
c[x] = c[u] ^ 1;
dfs(x);
}
}
};
int cnt=0;
for(int i=0;i<n;i++){
if(used[i]) continue;
dfs(i);
for(int t=0;t<2;t++){
for(auto x : tt[t]){
tree.sett(l[x], r[x]);
tree.sett(r[x], l[x]);
}
for(auto x : tt[t]){
auto m = tree.get(l[x], r[x]);
if(m[0] < l[x] || r[x] < m[1]){
cout<<0<<"\n";
return 0;
}
}
for(auto x : tt[t]){
tree.sett(l[x], l[x]);
tree.sett(r[x], r[x]);
} tt[t].clear();
} cnt++;
}
int res = 1;
while(cnt--){
res = res * 2ll % mod;
}
cout<<res<<"\n";
}
