#include <bits/stdc++.h>
using namespace std;
const int MOD = 1e9 + 7;
const int MAX_N = 1e6 + 5;
const int INF = 1e9 + 7;
int A[MAX_N], B[MAX_N];
vector <int> graph[MAX_N];
int color[MAX_N];
struct Node {
int far, idx;
Node() : far(-INF), idx(-INF) {}
Node(int f, int i) : far(f), idx(i) {}
Node operator+(const Node &o) const {
if(far > o.far) {
return Node(far, idx);
}
return o;
}
}tree[8 * MAX_N];
void build(int idx, int l, int r) {
tree[idx] = Node();
if(l == r) {
return;
}
int mid = (l + r) / 2;
build(idx * 2, l, mid);
build(idx * 2 + 1, mid + 1, r);
}
void update(int idx, int l, int r, int q, pair <int, int> v) {
if(l == r) {
if(tree[idx].far < v.first) {
tree[idx].far = v.first;
tree[idx].idx = v.second;
}
return;
}
int mid = (l + r) / 2;
if(q <= mid) {
update(idx * 2, l, mid, q, v);
}
else {
update(idx * 2 + 1, mid + 1, r, q, v);
}
tree[idx] = tree[idx * 2] + tree[idx * 2 + 1];
}
Node query(int idx, int l, int r, int ql, int qr) {
if(r < ql or qr < l) {
return Node();
}
if(ql <= l and r <= qr) {
return tree[idx];
}
int mid = (l + r) / 2;
return query(idx * 2, l, mid, ql, qr) + query(idx * 2 + 1, mid + 1, r, ql, qr);
}
void dfs(int u, int c) {
color[u] = c;
for(auto v : graph[u]) {
if(color[v] == -1) {
dfs(v, c ^ 1);
}
else {
if(color[u] == color[v]) {
cout << 0;
exit(0);
}
}
}
}
int main() {
cin.tie(nullptr)->sync_with_stdio(false);
int N, S;
cin >> N;
vector <int> vec;
for(int i = 1; i <= N; i++) {
cin >> A[i] >> B[i];
vec.push_back(A[i]);
vec.push_back(B[i]);
}
sort(vec.begin(), vec.end());
vec.resize(unique(vec.begin(), vec.end()) - vec.begin());
S = vec.size();
for(int i = 1; i <= N; i++) {
A[i] = lower_bound(vec.begin(), vec.end(), A[i]) - vec.begin() + 1;
B[i] = lower_bound(vec.begin(), vec.end(), B[i]) - vec.begin() + 1;
}
build(1, 1, S);
for(int i = 1; i <= N; i++) {
update(1, 1, S, A[i], make_pair(B[i], i));
}
for(int i = 1; i <= N; i++) {
Node nxt = query(1, 1, S, A[i] + 1, B[i] - 1);
if(nxt.idx != -INF and nxt.far > B[i]) {
graph[i].push_back(nxt.idx);
graph[nxt.idx].push_back(i);
}
}
build(1, 1, S);
for(int i = 1; i <= N; i++) {
update(1, 1, S, B[i], make_pair(-A[i], i));
}
for(int i = 1; i <= N; i++) {
Node nxt = query(1, 1, S, A[i] + 1, B[i] - 1);
if(nxt.idx != -INF and -nxt.far < A[i]) {
graph[i].push_back(nxt.idx);
graph[nxt.idx].push_back(i);
}
}
memset(color, -1, sizeof(color));
int cnt_cmp = 0;
for(int i = 1; i <= N; i++) {
if(color[i] == -1) {
cnt_cmp++;
dfs(i, 0);
}
}
int ans = 1;
while(cnt_cmp--) {
ans *= 2;
ans %= MOD;
}
cout << ans;
return 0;
}
