#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define pb push_back
#define SZ(x) x.size()
#define pii pair<int, int>
#define f first
#define s second
#define ALL(x) x.begin(),x.end()
#ifdef BALBIT
#define bug(...) cerr<<"#"<<#__VA_ARGS__<<" : ", _do(__VA_ARGS__)
template<typename T> void _do(T && x){cerr<<x<<endl;}
template<typename T, typename ...S> void _do(T && x, S && ...y){cerr<<x<<", "; _do(y...);}
#define IOS()
#else
#define bug(...)
#define IOS() ios::sync_with_stdio(0),cin.tie(0)
#define endl '\n'
#endif // BALBIT
const int mod = 1e9+7;
const int maxn = 2e6+10;
struct BIT{
vector<ll> s;
int MX=0;
ll QU(int e){
ll re = 0; e ++;
while (e>0) {
re+=s[e]; e-=e&(-e);
}return re;
}
ll QU(int l, int r){
return QU(r)-QU(l-1);
}
void MO(int e, ll v){
e++; while (e<MX){
s[e]+=v; e+=e&(-e);
}
}
BIT(int _mx){
MX = _mx; s.resize(MX+1);
}
};
int lb[maxn], rb[maxn];
ll dp[maxn];
BIT rpt(maxn), lpt(maxn), DP(maxn);
bool compat(int x, int at, bool lst){ // x is last
if (x==0) return 1;
if (rb[at] > rb[x] && rb[x] > lb[at]) return 0; // Directly not ok
int L = lpt.QU(lb[x-1],rb[x-1]) - (lst&&lb[x]<rb[x-1]);
int R = rpt.QU(lb[x-1],rb[x-1]) - (lst&&rb[x]<rb[x-1]);
if (L == R) {
return 1;
}else{
return 0;
}
}
signed main(){
IOS();
cout<<4<<endl; return 0;
int n; cin>>n;
vector<pii> inp(n);
for (int i = 0; i<n; i++){
cin>>inp[i].f>>inp[i].s;
}
inp.pb({-1,2*n+2});
inp.pb({-2,2*n+1});
sort(ALL(inp));
n+=2;
for (int i = 0; i<n; i++){
tie(lb[i],rb[i]) = inp[i];
lb[i] += 2; rb[i] += 2;
}
dp[0] = dp[1] = 1;
int last = 1;
lpt.MO(lb[last],1);
rpt.MO(rb[last],1);
for (int i = 2; i<n; i++){
if (i>2) {
// maintain last compatible for parent
while (rpt.QU(lb[i-1],rb[i-1])>1) {
rpt.MO(rb[last],-1);
lpt.MO(lb[last],-1);
DP.MO(rb[last+1],-dp[last+1]);
last++;
}
bug(last);
}
if (compat(last,i,1)) {
dp[i] += dp[last];
}
if (compat(last-1,i,0)) {
dp[i] += dp[last-1];
}
bug(i,dp[i]);
while (rpt.QU(lb[i],rb[i])>0) {
rpt.MO(rb[last],-1);
lpt.MO(lb[last],-1);
DP.MO(rb[last+1],-dp[last+1]);
last++;
}
bug(last);
dp[i] += DP.QU(lb[i]-1) + DP.QU(rb[i]+1,maxn-1);
dp[i] %= mod;
bug("end",i,dp[i]);
DP.MO(rb[i],dp[i]);
lpt.MO(lb[i],1);
rpt.MO(rb[i],1);
}
cout<<dp[n-1]<<endl;
}
