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#include <bits/stdc++.h>
using namespace std;

#define st first
#define nd second

typedef long long int lli;

const int MAXN = 500005;
const lli MOD = 1000000007;

lli pot(lli a, lli n) {
    if (n == 0)
        return 1;
    
    if (n%2 == 0)
        return pot((a*a)%MOD, n/2);
    else
        return (a*pot(a, n-1)) % MOD;
}

lli rev(lli a) {
    return pot(a, MOD-2);
}

/*set<pair<int, int>> occ;

pair<int, int> get_int(int x) {
    if (occ.empty())
        return {-1, -1};
    
    auto it = occ.upper_bound({x, x});
    
    if (it == occ.begin())
        return {-1, -1};
    
    it--;
    
    auto p = *it;
    
    if (p.st <= x && x <= p.nd)
        return p;
    else
        return {-1, -1};
}

void add_int(int a, int b) {
    auto it = occ.upper_bound({a, a});
    
    if (it != occ.begin())
        it--;
    
    while (it != occ.end()) {
        auto p = *it;
        
        if (p.st > b)
            break;
    }
    
    occ.insert({a, b});
}*/

lli dp[MAXN*16];

lli dp_get(int x, int tar, int pp, int kk) {
    if (dp[x] != 0)
        return dp[x];
    
    if (kk == pp+1)
        return dp[x];
    
    int s = (pp+kk)/2;
    
    if (tar < s)
        return dp_get(2*x, tar, pp, s);
    else
        return dp_get(2*x+1, tar, s, kk);
}

void dp_set(int x, lli v, int p, int k, int pp, int kk) {
    if (p == pp && k == kk) {
        dp[x] = v;
        return;
    }
    
    if (dp[x] != 0) {
        dp[2*x] = dp[x];
        dp[2*x+1] = dp[x];
        dp[x] = 0;
    }
    
    int s = (pp+kk) / 2;
    
    if (k <= s)
        return dp_set(2*x, v, p, k, pp, s);
    else if (s <= p)
        return dp_set(2*x+1, v, p, k, s, kk);
    
    dp_set(2*x, v, p, s, pp, s);
    dp_set(2*x+1, v, s, k, s, kk);
}

vector<int> d[MAXN];
vector<lli> all_ups[MAXN];

int prp[MAXN][2];

int prp_cnt = 0;

void dfs(int x) {
    prp[x][0] = prp_cnt++;
    
    for (int a : d[x])
        dfs(a);
    
    prp[x][1] = prp_cnt++;
}

int vis_cnt[MAXN];

int count_ancestors(int x, int id) {
    if (vis_cnt[x] == id)
        return 0;
    
    vis_cnt[x] = id;
    int res = 1;
    
    for (int a : all_ups[x])
        res += count_ancestors(a, id);
    
    return res;
}

int main() {
    int n;
    scanf("%d", &n);
    
    int pd = 2;
    while (pd <= 2*n+5)
        pd *= 2;
    
//     for (int i=0; i<=2*pd+10; i++) {
//         dp[i] = -1;
//     }
    
    for (int i=1; i<=n; i++) {
        int a, b;
        scanf("%d%d", &a, &b);
        lli l = dp_get(1, a, 0, pd);
        lli p = dp_get(1, b, 0, pd);
        dp_set(1, i, a, b+1, 0, pd);
        
        d[l].push_back(i);
        all_ups[l].push_back(i);
        all_ups[p].push_back(i);
    }
    
//     for (int i=0; i<=n; i++) {
//         printf("%d: ", i);
//         for (int x : d[i])
//             printf(" %d", x);
//         printf("\n");
//     }

    dfs(0);
    
    lli res = 0;
    
    for (int i=1; i<=n; i++) {
        int x = count_ancestors(i, i);
        
//         printf(" %d %d\n", i, x);
        
        res = (res + rev(x)) % MOD;
    }
    
    printf("%lld\n", res);
    
    return 0;
}