#include <bits/stdc++.h>
using namespace std;
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
#define ordered_set tree<int, null_type,less_equal<int>, rb_tree_tag,tree_order_statistics_node_update>
// #pragma GCC optimize("Ofast,unroll-loops,fast-math")
// #pragma GCC target("popcnt,avx")
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef pair<ll,ll> pll;
#define sz size()
#define ff first
#define ss second
#define all(a) a.begin(),a.end()
#define pb push_back
const int mod = ll(1e9)+7; //(b + (a%b)) % b (to mod -1%(10^9+7) correctly in c++ its -1 but its suppose to be 10^9+6
const ll MOD = 998244353; // (a%mod)*(binpow(b,mod-2,mod) = (a/b)%mod
const int N = ll(1e7)+100;
const int M = ll(2e5) + 100;
const long long inf = 5e18;
//const long double eps = 1e-15L;
ll lcm(ll a, ll b) { return (a / __gcd(a,b))*b; }
ll binpow(ll a, ll b, ll m) { ll res=1; a %= m; while(b>0){ if(b&1)res=(res * a) % m; a=(a * a) % m; b/=2; } return res%m;}
void Freopen(string Key){ freopen((Key+".in").c_str(), "r", stdin); freopen((Key+".out").c_str(), "w", stdout); }
int add(int x) {
if(x > mod) return x - mod;
return x;
}
int n, a[505], b[505], t[N], lv[N], rv[N], timer = 1;
void update(int v, int tl, int tr, int l, int r, int sum = 0) {
if(tl > r || l > tr) return;
if(tl == tr) {
t[v] = add(t[v] + sum + 1);
return;
}
int tm = (tl + tr) / 2;
if(!lv[v]) lv[v] = ++ timer;
if(!rv[v]) rv[v] = ++ timer;
update(rv[v], tm + 1, tr, l, r, add(sum + t[lv[v]]));
update(lv[v], tl, tm, l, r, sum);
t[v] = add(t[lv[v]] + t[rv[v]]);
}
void Baizho() {
cin>>n;
for(int i = 1; i <= n; i ++) {
cin>>a[i]>>b[i];
update(1, 1, 1e9, a[i], b[i]);
}
cout<<t[1]<<"\n";
}
signed main() {
// Freopen("nondec");
ios_base::sync_with_stdio(false);
cin.tie(0);cout.tie(0);
// precalc();
int ttt = 1;
// cin>>ttt;
for(int i=1; i<=ttt; i++) {Baizho(); }
}
