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#include <bits/stdc++.h>
using namespace std;
#define rep(a, b) for (int a = 0; a < (b); a++)
#define rep1(a, b) for (int a = 1; a <= (b); a++)
#define all(x) (x).begin(), (x).end()
using ll = long long;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
const int MOD = 1e9 + 7;

#define LOCAL false

const int MAX_N = 1<<19; // >500k
int n;

const int TREE_SIZE = MAX_N<<1;
pii tree[TREE_SIZE];
int t = 1;
void setrange(int l, int r, int x) {
    if (l > r) return;
    for (l += MAX_N, r += MAX_N+1; l<r; l>>=1, r>>=1) {
        if (l&1) tree[l++] = {x, t};
        if (r&1) tree[--r] = {x, t};
    }
    t++;
}
int getval(int x) {
    int val = 0;
    int maxt = 0;
    x += MAX_N;
    while (x) {
        if (tree[x].second > maxt) {
            val = tree[x].first;
            maxt = tree[x].second;
        }
        x >>= 1;
    }
    return val;
}

vector<int> graph[MAX_N];
int anccnt[MAX_N];
bool vis[MAX_N];
void dfs(int v, bool root = true) {
    vis[v] = true;
    if (!root) anccnt[v]++;
    for (int to: graph[v]) if (!vis[to]) dfs(to, false);
}

int fastpow(int n, int p) {
    int ans = 1;
    while (p) {
        if (p&1) ans = ((ll)ans*n)%MOD;
        n = ((ll)n*n)%MOD;
        p >>= 1;
    }
    return ans;
}

int main() {
    ios_base::sync_with_stdio(0); cin.tie(0);
    if (LOCAL) {
        ignore=freopen("io/in", "r", stdin);
        ignore=freopen("io/out", "w", stdout);
    }

    cin >> n;
    int l, r;
    rep1(v, n) {
        cin >> l >> r;
        int lv = getval(l);
        int rv = getval(r);
        if (lv != 0) graph[v].push_back(lv);
        if (rv != 0 && rv != lv) graph[v].push_back(rv);
        setrange(l+1, r-1, v);
    }

    rep1(v, n) {
        rep1(v2, n) vis[v2] = false;
        dfs(v);
    }

    int ans = 0;
    rep1(v, n) ans = (ans+fastpow(anccnt[v]+1, MOD-2))%MOD;
    cout << ans << '\n';

    return 0;
}