#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
#define S second
#define F first
#define all(x) (x).begin(),(x).end()
#define sz size()
#define Yes cout << "YES" << endl
#define No cout << "NO" << endl
#define pb(x) push_back(x);
#define endl '\n'
#define fast ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
const int N=502;
ll INF=INT_MAX,mod=1e9+7;
int TT=1;
ll power(ll x, unsigned int y)
{
ll res = 1;
x = x; // % mod;
if (x == 0) return 0;
while (y > 0)
{
if (y & 1) res = (res*x) ; // % mod;
y = y>>1;
x = (x*x) ; // % mod;
}
return res;
}
ll n; ll a[N];
ll dp[N][N];
map<ll,ll> mp;
void solve()
{
cin >> n;
for(int i = 1; i <= n; i++) cin >> a[i] >> a[i];
for(int i = 1; i <= n; i++) mp[a[i]] = 1;
ll coml = 1;
for(auto it:mp)
{
mp[it.F] = coml++;
}
dp[0][0] = 1;
for(int i = 1; i <= n; i++)
{
ll x = mp[a[i]];
for(int j = 0; j <= n; j++) dp[i][j] = dp[i-1][j];
for(int j = 0; j < x; j++)
{
dp[i][x] = (dp[i-1][j] + dp[i][x])%mod;
}
}
ll ans = 0;
for(int i = 1; i <= n; i++) ans = (ans+dp[n][i])%mod;
cout << ans << endl;
}
int main(){
//freopen("friday.in","r",stdin);
//freopen("friday.out","w",stdout);
fast;
while(TT--)
solve();
return 0;
}
