#include <bits/stdc++.h>
using namespace std;
const int mod = (int) 1e9 + 7;
template<typename T>
class segtree {
private:
int b;
vector<T> tr;
public:
segtree() {}
segtree(int n) {
b = 1;
while (b < n) {
b <<= 1;
}
tr.assign(2 * b, 0);
}
void upd(int i, const T& val) {
tr[i += b] = val;
for (i >>= 1; i > 0; i >>= 1) {
tr[i] = (tr[i << 1] + tr[i << 1 | 1]) % mod;
}
}
T qry(int l, int r) {
T ans = 0;
for (l += b, r += b; l <= r; l >>= 1, r >>= 1) {
if (l & 1) ans = (ans + tr[l++]) % mod;
if (!(r & 1)) ans = (ans + tr[r--]) % mod;
}
return ans;
}
};
int main() {
ios::sync_with_stdio(false);
cin.tie(0);
int n;
cin >> n;
vector<int> a(n), b(n), se;
for (int i = 0; i < n; i++) {
cin >> a[i] >> b[i];
for (int j = a[i]; j <= b[i]; j++) {
se.push_back(j);
}
}
sort(se.begin(), se.end());
int idd = 1;
map<int, int> mp;
for (int i = 0; i < (int) se.size(); i++) {
if (i == 0 || se[i] != se[i - 1]) {
mp[se[i]] = idd++;
}
}
for (int i = 0; i < n; i++) {
a[i] = mp[a[i]];
b[i] = mp[b[i]];
}
segtree<long long> st(idd);
vector<long long> dp(idd, 0);
dp[0] = 1;
st.upd(0, 1);
for (int i = 0; i < n; i++) {
for (int j = b[i]; j >= a[i]; j--) {
dp[j] = (dp[j] + st.qry(0, j - 1)) % mod;
st.upd(j, dp[j]);
}
}
long long sum = 0;
for (int i = 1; i < idd; i++) {
sum = (sum + dp[i]) % mod;
}
cout << sum << '\n';
return 0;
}
