#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
using pii = pair<int, int>;
using pll = pair<long long, long long>;
using ull = unsigned long long;
#define X first
#define Y second
#define SZ(x) int(x.size())
#define all(x) x.begin(), x.end()
#define mins(a,b) (a = min(a,b))
#define maxs(a,b) (a = max(a,b))
#define pb push_back
#define Mp make_pair
#define lc id<<1
#define rc lc|1
#define mid ((l+r)/2)
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
const ll INF = 1e9 + 23;
const ll MOD = 1e9 + 7;
const int MXN = 2e6 + 2;
const int LOG = 23;
int n, ptr[MXN<<2];
pii A[MXN];
vector<int> seg[MXN<<2];
void add_seg(int p, int x, int l=1, int r=2*n+1, int id=1) {
if(r-l==1){
seg[id].pb(x);
return;
}
if(p<mid) add_seg(p, x, l, mid, lc);
else add_seg(p, x, mid, r, rc);
}
void build(int l=1, int r=2*n+1, int id=1) {
if(r-l==1) return;
build(l, mid, lc);
build(mid, r, rc);
int i=0, j=0;
while(i<SZ(seg[lc]) && j<SZ(seg[rc]))
seg[id].pb(A[seg[lc][i]].X<A[seg[rc][j]].X ? seg[lc][i++] : seg[rc][j++]);
while(i<SZ(seg[lc])) seg[id].pb(seg[lc][i++]);
while(j<SZ(seg[rc])) seg[id].pb(seg[rc][j++]);
}
vector<pii> g[MXN];
inline void add_edge(int u, int v, int w) {
g[u].pb(Mp(v,w));
g[v].pb(Mp(u,w));
}
void add(int s, int e, int i, int l=1, int r=2*n+1, int id=1) {
if(seg[id].empty() || A[seg[id][0]].X>=A[i].X) return;
if(s<=l && r<=e) {
add_edge(seg[id][0], i, 3);
while(ptr[id]+1<SZ(seg[id]) && A[seg[id][ptr[id]+1]].X<A[i].X)
add_edge(seg[id][0], seg[id][++ptr[id]], 0);
return;
}
if(s<mid) add(s, e, i, l, mid, lc);
if(e>mid) add(s, e, i, mid, r, rc);
}
int col[MXN];
void dfs(int v, int c) {
col[v] = c;
for(auto [u, w] : g[v])
if(!col[u]) dfs(u, c^w);
else if(col[u] != (c^w)) {
cout << "0\n";
exit(0);
}
}
void Main() {
cin >> n;
for(int i=1; i<=n; i++) {
cin >> A[i].X >> A[i].Y;
add_seg(A[i].Y, i);
}
build();
for(int i=1; i<=n; i++) add(A[i].X, A[i].Y, i);
int ans=1;
for(int i=1; i<=n; i++)
if(!col[i]) {
dfs(i, 1);
ans <<= 1;
if(ans>=MOD) ans -= MOD;
}
cout << ans << '\n';
}
int32_t main() {
cin.tie(0); cout.tie(0); ios_base::sync_with_stdio(0);
int T = 1;
// cin >> T;
while(T--) Main();
return 0;
}
