#include <bits/stdc++.h>
using namespace std;
#define TRACE(x) cerr << #x << " :: " << x << endl
#define _ << " " <<
#define SZ(x) ((int)(x).size())
#define ALL(x) (x).begin(),(x).end()
#define FOR(i,a,b) for(int i=(a);i<=(b);++i)
#define RFOR(i,a,b) for(int i=(a);i>=(b);--i)
typedef long long ll;
typedef pair<int,int> ii;
const int MN = 1e6+5;
const int mod = 1e9+7;
int N;
ii C[MN];
ll ans;
vector<int> al[MN];
int col[MN];
void dfs(int u, int c) {
if (!ans) return;
col[u] = c;
for (int& v : al[u]) {
if (col[v] == -1) dfs(v,!c);
else if (col[v] != !c) ans = 0;
}
}
int main() {
ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
cin >> N;
FOR(i,1,N){
int a, b; cin >> a >> b;
C[i] = ii(a,b);
}
FOR(i,1,N) FOR(j,1,N) if (i != j) {
if (C[i].first < C[j].first && C[i].second > C[j].first && C[i].second < C[j].second) {
al[i].push_back(j);
al[j].push_back(i);
}
}
ans = 1;
memset(col,-1,sizeof col);
FOR(i,1,N) if (col[i] == -1) {
//TRACE(i);
dfs(i,0);
if (!ans) break;
ans = 2*ans % mod;
}
cout << ans << '\n';
}
