#include <bits/stdc++.h>
typedef long long ll;
using namespace std;
const ll MOD = 1e9 + 7;
ll BIG = 1000002;
int main() {
ios::sync_with_stdio(false);
cin.tie(0);
int n;
cin >> n;
vector<ll> a(n), b(n);
bool st1 = true;
for(int i = 0; i < n; i++) {
cin >> a[i] >> b[i];
if(a[i] != b[i]) st1 = false;
}
if(st1) {
vector<ll> sums(n, 1);
for(int i = 1; i < n; i++) {
for(int j = 0; j < i; j++) {
if(a[j] < a[i]) sums[i] += sums[j];
sums[i] %= MOD;
}
}
ll ans = 0;
for(int i = 0; i < n; i++) ans += sums[i];
cout << ans % MOD << '\n';
return 0;
}
vector<unsigned int> nums(BIG/10);
nums[0] = 1;
for(int i = 0; i < n; i++) {
ll g = 0;
for(int j = 0; j < a[i]; j++) {
g += nums[j];
g %= MOD;
}
for(int j = a[i]; j <= b[i]; j++) {
g += nums[j];
nums[j] += (g - nums[j]);
nums[j] += MOD;
nums[j] %= MOD;
g %= MOD;
}
}
ll ans = 0;
for(int i = 1; i < BIG; i++) {
ans += nums[i];
ans %= MOD;
}
cout << ans << '\n';
}
