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#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
#define int long long
#define st first
#define nd second
#define pb push_back
#define mp make_pair
#define rep(i,a,b) for(ll i=(ll)a;i<=(ll)b;++i)
#define all(a) a.begin(),a.end()
#define sz(x) (int)(x).size()
const int mxN = 5e5+7, MOD = 1e9+7;

int inv(int a, int w = MOD-2){
    int res = 1;
    while(w){
        if(w&1) res = (res * a)%MOD;
        a = (a*a)%MOD;
        w /= 2;
    }
    return res;
}

vector<int> graf[mxN];
pair<int,int> x[mxN];
int dp[mxN];

bitset<64> bs[mxN];

int32_t main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);

    int n; cin >> n;
    set<pair<int,int>> s;

    rep(i,1,n) cin >> x[i].st >> x[i].nd;
    reverse(x+1,x+n+1);

    rep(i,1,n){
        auto [a,b] = x[i];
        auto it = s.upper_bound({a,0});
        while(it != s.end()){
            if((*it).st < a || b < (*it).st) break;
            graf[i].pb((*it).nd);
            //cout << (*it).nd << " " << i << "\n";
            //cout << i << " " << (*it).nd << "\n";
            it = s.erase(it);
        }
        s.insert({a, i});
        s.insert({b, i});
    }

    rep(i,1,n){
        sort(all(graf[i]));
        graf[i].erase(unique(all(graf[i])), graf[i].end());
    }

    for(int k=1;k<=n;k+=64){
        //przedzial od k do k+63
        rep(i,1,n) bs[i].reset();

        rep(i,1,n){
            if(k <= i && i <= k+63) bs[i][i-k] = 1;
            for(auto j : graf[i]) bs[i] |= bs[j];
            dp[i] += bs[i].count();
        }

    }
    int res = 0;
    rep(i,1,n) res = (res + inv(dp[i]))%MOD;
    cout << res << "\n";
}