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#include <bits/stdc++.h>

#define ll long long
#define fors(u, n, s) for(ll u = (s); u < (n); u++)
#define foru(u, n) fors(u, n, 0)
#define vec vector
#define pb push_back
#define f first
#define s second
#define ir(a, b, x) (((a) <= (x)) && ((x) <= (b)))
#define pint pair<int, int>
#define us unsigned

using namespace std;

const int N = 6e5;
const int N_ = (1<<20);
int n;

int tree_mem[2*N_];

int query(int x) {
	int out = -1;
	for (x += N_; x > 0; x >>= 1) out = max(out, tree_mem[x]);
	return out;
}

void modify(int a, int b, int m) {
	b++;
	for (a += N_, b += N_; a < b; a >>= 1, b >>= 1) {
    if (a&1) {
    	tree_mem[a] = max(tree_mem[a], m);
    	a++;
    }
    if (b&1) {
    	b--;
    	tree_mem[b] = max(tree_mem[b], m);
    }
  }
}

int left_edge[N];
int right_edge[N];
int left_child[N];
int right_child[N];

const int M = 1e9+7;

int inv(int a) {
  return a <= 1 ? a : M - (long long)(M/a) * inv(M % a) % M;
}

int add_to_subtree[N];

const int LOG_N=20;

int exp_jmp_l[N][LOG_N];
int exp_jmp_r[N][LOG_N];

int jmp_l(int x, int p){
	if(x == -1) return -1;
	return exp_jmp_l[x][p];
}

int jmp_r(int x, int p){
	if(x == -1) return -1;
	return exp_jmp_r[x][p];
}

int find_intersection(int l, int r){
	if(l <= r) goto skip;
	for(int lk = LOG_N-1; lk>=0; lk--){
		int l_ = jmp_r(l, lk);
		if(l_ > r) l = l_;
	}
	l = jmp_r(l, 0);
	skip:

	for(int rk = LOG_N-1; rk>=0; rk--){
		int r_ = jmp_l(r, rk);
		if(r_ >= l) r = r_;
	}

	if(r == -1) return -1;
	if(l == -1) return -1;
	if(l == r) return l;
	
	if(l == jmp_l(r, 0)) return l;
	if(right_edge[l] > left_edge[r]) return l;

	
	for(int lk = LOG_N-1; lk>=0; lk--){
		int l_ = jmp_r(l, lk);
		if(l_==-1) continue;

		if(r < l_){
			l = l_;
			continue;
		}
		
		int r_ = r;
		for(int rk = LOG_N-1; rk>=0; rk--){
			int r__ = jmp_l(r_, rk);
			if(r__ > l_) r_ = r__;
		}
		if(l_ == jmp_l(r_, 0)) continue;
		if(right_edge[l_] > left_edge[r_]) continue;
		l = l_;
	}

	int r_ = r;
	for(int rk = LOG_N-1; rk>=0; rk--){
		int r__ = jmp_l(r_, rk);
		if(r__ > l) r_ = r__;
	}
	
	return jmp_r(l, 0);
}

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

	foru(i, 2*N_) tree_mem[i] = -1;

	cin >> n;
	
	foru(i, n) {
		int a, b; cin >> a >> b;
		a--; b--;

		left_edge[i] = a;
		right_edge[i] = b;
		
		left_child[i] = query(a);
		right_child[i] = query(b);
		modify(a+1, b-1, i);

		exp_jmp_l[i][0]=left_child[i];
		exp_jmp_r[i][0]=right_child[i];
	}

	fors(k, LOG_N, 1) foru(i, n){
		exp_jmp_l[i][k]=jmp_l(jmp_l(i, k-1), k-1);
		exp_jmp_r[i][k]=jmp_r(jmp_r(i, k-1), k-1);
	}

	foru(i, n) add_to_subtree[i]=1;

	for(int i = n-1; i>=0; i--){
		int l = left_child[i];
		int r = right_child[i];

		if(l != -1) add_to_subtree[l] += add_to_subtree[i];
		if(r != -1) add_to_subtree[r] += add_to_subtree[i];

		int inter = find_intersection(l, r);
		if(inter != -1) add_to_subtree[inter] -= add_to_subtree[i];
	}
 
	int ans = 0;

	foru(i, n) {
		ans += inv(add_to_subtree[i]);
		if(ans >= M) ans -= M;
	}

	cout << ans << endl;

}