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#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef pair<int, int> pii;

const int N = 5e5+100;
const int K = 20;
const int MOD = 1e9+7;
const int INF = 1e9;

struct segtree {
    vector<int> t, lz;

    void init(int sz) {
        t.assign(4*sz+10, 0);
        lz.assign(4*sz+10, -1);
    }

    void push(int v) {
        lz[2*v]=lz[v], lz[2*v+1]=lz[v];
        t[2*v]=lz[v], t[2*v+1]=lz[v];
        lz[v]=-1;
    }

    void upd(int v, int l, int r, int ql, int qr, int vl) {
        if (l > qr || r < ql) return;
        if (l >= ql && r <= qr) {
            lz[v]=vl; t[v]=vl;
            if (l < r) push(v);
            return;
        } int m=(l+r)/2; 
        if (lz[v] != -1) push(v);
        upd(2*v, l, m, ql, qr, vl), upd(2*v+1, m+1, r, ql, qr, vl);
    }

    int que(int v, int l, int r, int p) {
        if (l == r) return t[v];
        int m=(l+r)/2; 
        if (lz[v] != -1) push(v);
        if (p <= m) return que(2*v, l, m, p);
        return que(2*v+1, m+1, r, p);
    }
};

ll n, l[N], r[N], f[N], upl[K][N], upr[K][N], pf[N], indeg[N];

pii g[N];

ll bpw(ll x, ll n) {
    if (n == 0) return 1;
    ll c=bpw(x, n/2);
    c=(c*c)%MOD;
    if (n&1) return (c*x)%MOD;
    return c;
}

int mv(int rx, int lp) {
    if (lp > rx) return rx;
    for (int i=K-1; i>=0; --i) {
        if (upl[i][rx] > lp) rx=upl[i][rx];
    } return rx;
}

int com(int lx, int rx) {
    if (lx == rx) return lx;

    int lc=lx;
    for (int j=K-1; j>=0; --j) {
        if (upr[j][lc] > rx) lc=upr[j][lc];
    }

    if (upr[0][lc] == rx) return rx;

    int rc=rx;
    for (int j=K-1; j>=0; --j) {
        if (upl[j][rc] > lx) rc=upl[j][rc];
    }

    if (upl[0][rc] == lx) return lx;

    for (int i=K-1; i>=0; --i) {
        int lp=upr[i][lx];
        int x=mv(rx, lp);
        if (x == lp) continue;
        if (r[lp] < l[x]) lx=lp;
    }

    return upr[0][lx];
}

int com2(int lx, int rx) {
    if (lx == rx) return lx;

    int lc=lx;
    for (int j=K-1; j>=0; --j) {
        if (upr[j][lc] > rx) lc=upr[j][lc];
    }

    if (upr[0][lc] == rx) return rx;

    int rc=rx;
    for (int j=K-1; j>=0; --j) {
        if (upl[j][rc] > lx) rc=upl[j][rc];
    }

    if (upl[0][rc] == lx) return lx;

    for (int i=n; i>=1; --i) {
        int lc=lx, rc=rx;
        for (int j=K-1; j>=0; --j) {
            if (upr[j][lc] > i) lc=upr[j][lc];
            if (upl[j][rc] > i) rc=upl[j][rc];
        }

        if (upr[0][lc] == upl[0][rc] && upr[0][lc] == i) return i;
    } return 0;
}

void solve() {
    cin>>n;
    for (int i=1; i<=n; ++i) cin>>l[i]>>r[i];
    l[0]=-INF, r[0]=INF;

    if (n == 1) {
        cout<<1<<"\n";
        return;
    }

    segtree t; t.init(2*n+10);

    for (int i=1; i<=n; ++i) {
        int x=t.que(1, 1, 2*n, l[i]);
        g[i].first=x; ++indeg[x];
        x=t.que(1, 1, 2*n, r[i]);
        g[i].second=x; ++indeg[x];
        t.upd(1, 1, 2*n, l[i], r[i], i);
    }

    for (int i=1; i<=n; ++i) {
        assert(g[i].first != -1 && g[i].second != -1);

        upl[0][i]=g[i].first, upr[0][i]=g[i].second;
        for (int k=1; k<K; ++k) {
            upl[k][i]=upl[k-1][upl[k-1][i]];
            upr[k][i]=upr[k-1][upr[k-1][i]];
        } ++pf[i];
    }

    queue<int> q;
    for (int i=1; i<=n; ++i) {
        if (indeg[i] == 0) q.push(i);
    }

    while (!q.empty()) {
        int v=q.front(); q.pop();

        if (g[v].first == g[v].second) {
            int u=g[v].first;
            indeg[u]-=2;
            pf[u]+=pf[v];
            if (indeg[u] == 0) q.push(u);
        } else {
            int u=g[v].first;
            --indeg[u], pf[u]+=pf[v];
            if (indeg[u] == 0) q.push(u);

            u=g[v].second;
            --indeg[u], pf[u]+=pf[v];
            if (indeg[u] == 0) q.push(u);
            pf[com(g[v].first, g[v].second)]-=pf[v];
        }
    }
   
    ll ans=0;
    for (int i=1; i<=n; ++i) (ans+=bpw(pf[i], MOD-2))%=MOD;
    cout<<ans<<"\n";
}

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

    int t=1; //cin>>t;
    while (t--) solve();
}