#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define endl '\n'
#define INF 1e9+7
#define all(x) x.begin(),x.end()
using namespace std;
using namespace __gnu_pbds;
using ll=long long;
using pii=pair<int,int>;
using ppi=pair<int,pii>;
using oset=tree<int,null_type,less<int>,rb_tree_tag,tree_order_statistics_node_update>;
template<typename T>
void _print(vector<T> x) {cerr<<"{"; for(auto e:x) cerr<<e<<","; cerr<<"}";}
void _print(pii x) {cerr<<"{"<<x.first<<","<<x.second<<"}";}
template<typename T>
void _print(T x) {cerr<<x;}
void dbg() {cerr<<endl;}
template<typename Head,typename... Tail>
void dbg(Head H,Tail... T) {
_print(H);
if(sizeof...(T)) cerr<<",";
else cerr<<"\"]";
dbg(T...);
}
#define debug(...) cerr<<"["<<#__VA_ARGS__<<"]:[\"",dbg(__VA_ARGS__)
//mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
const int md=INF;
ll dp[501][501];
int main () {
ios::sync_with_stdio(false); cin.tie(0);
int n; cin>>n;
vector<int> a(n);
for(int i=0;i<n;i++) cin>>a[i]>>a[i];
memset(dp,0,sizeof(dp));
dp[0][0]=1;
for(int i=1;i<n;i++) {
dp[i][i]=1;
for(int j=0;j<i;j++) {
if(a[i]>a[j]) {
for(int k=0;k<=j;k++) {
dp[i][j]=(dp[i][j]+dp[j][k])%md;
}
}
}
}
ll ans=0;
for(int i=0;i<n;i++) {
for(int j=0;j<=i;j++) {
// cout<<dp[i][j]<<" ";
ans=(ans+dp[i][j])%md;
}
// cout<<endl;
}
cout<<ans<<endl;
}
