#include <bits/stdc++.h>
using namespace std;
#define ff first
#define ss second
#define bl ' '
#define endl '\n'
#define all(v) (v).begin(), (v).end()
#define comp(v) (v).erase(unique(all(v)), (v).end())
#define lbd(v,x) lower_bound(all(v), (x))-(v).begin()
#define ubd(v,x) upper_bound(all(v), (x))-(v).begin()
typedef long long ll;
typedef pair<int, int> pi;
typedef pair<pi, int> pii;
typedef pair<int, pi> ipi;
typedef pair<pi, pi> pipi;
typedef pair<ll, ll> pll;
const int MAXN = 100100*10;
const ll MOD = 1e9+7;
const ll INF = 2e9;
pi arr[MAXN];
int out[MAXN*2];
int cnt;
int par[MAXN], col[MAXN];
int root(int x) {
if(par[x] == x) return x;
int rt = root(par[x]);
col[x] ^= col[par[x]];
return par[x] = rt;
}
void merge(int x, int y, int t) {//cout<<x<<bl<<y<<bl<<t<<endl;
int a = root(x), b = root(y);
if(a^b) {
col[a] = col[x]^col[y]^t;
par[a] = b; cnt--;
} else if(col[x]^col[y]^t) {
cnt = -1;
}
}
struct SegTree {
vector<int> tree[MAXN*2*4];
int mx[MAXN*2*4];
void init(int node, int s, int e) {
if(s == e) {
if(out[s]) tree[node].push_back(out[s]);
return;
}
int mid = s+e>>1;
init(node<<1, s, mid); init(node<<1|1, mid+1, e);
for(int &x : tree[node<<1]) tree[node].push_back(x);
for(int &x : tree[node<<1|1]) tree[node].push_back(x);
sort(all(tree[node]));
}
void update(int node, int s, int e, int l, int r, int t) {
if(e < l || r < s) return;
if(l <= s && e <= r) {
if(tree[node].size() && tree[node][0] < t) merge(tree[node][0], t, 1);
mx[node] = max(mx[node], t);
return;
}
int mid=s+e>>1;
update(node<<1, s, mid, l, r, t); update(node<<1|1, mid+1, e, l, r, t);
}
void construct(int node, int s, int e) {
for(int i=1; i<tree[node].size() && tree[node][i] < mx[node]; i++) {
merge(tree[node][i-1], tree[node][i], 0);
}
if(s == e) return;
int mid=s+e>>1;
construct(node<<1, s, mid), construct(node<<1|1, mid+1, e);
}
} seg;
int main() {
int n; cin>>n;
for(int i=1; i<=n; i++) cin>>arr[i].ff>>arr[i].ss;
sort(arr+1, arr+n+1); cnt = n;
for(int i=1; i<=n; i++) out[arr[i].ss] = i, par[i] = i;
seg.init(1, 1, n<<1);
for(int i=1; i<=n; i++) {
seg.update(1, 1, n<<1, arr[i].ff+1, arr[i].ss-1, i);
} seg.construct(1, 1, n<<1);
if(cnt < 0) cout << 0;
else {
ll res=1;
while(cnt--) res=(res<<1)%MOD;
cout<<res;
}
}
