#include <cstdio>
#include <algorithm>
#include <vector>
#include <stack>
#define PB push_back
#define X first
#define Y second
using namespace std;
typedef pair < int, int > pii;
const int N = 2e6 + 500;
const int MOD = 1e9 + 7;
vector < pii > v[N];
int col[N], bio[N], mog = 1, n;
int L[N], R[N], id[N], str[N];
int ima[N], stvar[N];
void dodaj(int x,int y,int razl = 1){
//printf("%d --%d-- %d\n", x, razl, y);
v[x].PB({y, razl});
v[y].PB({x, razl});
}
void dfs(int x){
if(bio[x]) return;
bio[x] = 1;
for(pii nxt : v[x]){
if(bio[nxt.X] && (col[x] ^ col[nxt.X]) != nxt.Y)
mog = 0;
if(!bio[nxt.X]){
col[nxt.X] = col[x] ^ nxt.Y;
dfs(nxt.X);
}
}
}
inline bool inter(int i,int j){
if(i == j) return 0;
if(L[i] < L[j] && R[i] < R[j] && R[i] > L[j])
return 1;
if(L[i] > L[j] && R[i] > R[j] && R[j] > L[i])
return 1;
return 0;
}
void obradi(int l,int r){
if(l >= r) return;
//printf("l = %d r = %d\n", l, r);
int mid = (l + r) / 2;
int lst = -1, cnt = 0, pos = 0;
vector < int > sljed;
// RIJESI SVE PREMA DESNO
for(int i = mid + 1;i <= r;i++){
if(L[id[i]] < l || R[id[i]] > r) continue;
if(str[i]){
if(L[id[i]] <= mid){
if(lst != -1 && cnt)
dodaj(id[i], lst, 0);
lst = id[i];
for(int x : sljed){
if(inter(lst, x))
dodaj(lst, x, 1);
}
sljed.clear();
cnt += pos;
}
else if(lst == -1 || L[id[i]] > R[lst])
pos--;
else
cnt--;
}
else{
sljed.PB(id[i]);
pos++;
}
}
//printf("rijesio desno\n");
lst = -1, cnt = 0, pos = 0;
sljed.clear();
// RIJESI SVE PREMA LIJEVO
for(int i = mid;i >= l;i--){
if(L[id[i]] < l || R[id[i]] > r) continue;
if(!str[i]){
if(R[id[i]] > mid){
if(lst != -1 && cnt)
dodaj(id[i], lst, 0);
lst = id[i];
for(int x : sljed){
if(inter(lst, x))
dodaj(lst, x, 1);
}
sljed.clear();
cnt += pos;
}
else if(lst == -1 || R[id[i]] < L[lst])
pos--;
else
cnt--;
}
else{
sljed.PB(id[i]);
pos++;
}
}
//printf("rijesio lijevo\n");
// RIJESI SVE KOJI SIJEKU
vector < int > niz;
for(int i = l;i <= mid;i++){
if(L[id[i]] < l || R[id[i]] > r) continue;
if(R[id[i]] > mid){
niz.PB(id[i]);
}
}
int cur = (int)niz.size();
for(int i = mid + 1;i <= r;i++){
if(L[id[i]] < l || R[id[i]] > r) continue;
if(L[id[i]] <= mid)
stvar[id[i]] = cur--;
}
stack < int > svi;
int zad = 1;int mx = -1;
for(int x : niz){
//printf("x = %d stvar[ %d ] = %d\n", x, x, stvar[x]);
if(mx != -1 && stvar[mx] > zad && stvar[x] > zad)
dodaj(mx, x, 0);
if(mx == -1 || stvar[x] > stvar[mx]){
mx = x;
}
if(mx != x)
dodaj(x, mx, 1);
ima[stvar[x]]++;
while(ima[zad])
zad++;
//while(!svi.empty() && stvar[svi.top()] < stvar[x]){
// if(stvar[svi.top()] > zad && stvar[x] > zad)
// dodaj(svi.top(), x, 0);
// svi.pop();
//}
//svi.push(x);
}
//printf("rijesio sredinu\n");
for(int i = 0;i <= (int)niz.size();i++)
ima[i] = 0;
obradi(l, mid); obradi(mid + 1, r);
}
int main(){
scanf("%d", &n);
for(int i = 1;i <= n;i++){
scanf("%d%d", L + i, R + i);
id[L[i]] = i, id[R[i]] = i;
str[R[i]] = 1;
}
obradi(1, 2 * n);
int komp = 0;
for(int i = 1;i <= n;i++){
komp += !bio[i]; dfs(i);
}
int sol = 1;
for(;komp--;) sol = (sol + sol) % MOD;
printf("%d\n", sol * mog);
}
