#include<bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#define x first
#define y second
#define pb push_back
#define mp make_pair
#define all(v) v.begin(),v.end()
#define sz(v) (int)v.size()
#define up_b upper_bound
#define low_b lower_bound
#define nl '\n'
using namespace std;
using namespace __gnu_pbds;
typedef long long ll;
typedef long double ld;
typedef tree<int,null_type,less<int>,rb_tree_tag,tree_order_statistics_node_update>ordered_set;
template<class T,int SZ> struct BIT{
T t[SZ];
void upd(int x,T y){
for(int i=x;i<SZ;i=(i|(i+1))){
t[i]+=y;
}
}
T pref(int x){
T res=0;
for(int i=x;i>=0;i=(i&(i+1))-1){
res+=t[i];
}
return res;
}
T get(int l,int r){
return pref(r)-pref(l-1);
}
};
template<class T,int SZ> struct ST{
T t[4*SZ];
void build(T a[],int v,int tl,int tr){
if(tl==tr){
t[v]=a[tl];
return ;
}
int tm=(tl+tr)/2;
build(a,v*2,tl,tm);
build(a,v*2+1,tm+1,tr);
t[v]=t[v*2]+t[v*2+1];
}
void upd(int v,int tl,int tr,int pos,T val){
if(tl==tr){
t[v]+=val;
return ;
}
int tm=(tl+tr)/2;
if(pos<=tm)upd(v*2,tl,tm,pos,val);
else upd(v*2+1,tm+1,tr,pos,val);
t[v]=t[v*2]+t[v*2+1];
}
T get(int v,int tl,int tr,int l,int r){
if(tl>r||l>tr)return 0;
if(l<=tl&&tr<=r)return t[v];
int tm=(tl+tr)/2;
return get(v*2,tl,tm,l,r)+get(v*2+1,tm+1,tr,l,r);
}
};
const int N=1e6+11;
const int M=1e3+11;
const int W=1e3+11;
const int inf=INT_MAX;
const ll INF=1e18;
const ll mod=1e9+7;
const ld EPS=1e-9;
const int dx[4]={0,0,1,-1};
const int dy[4]={1,-1,0,0};
int a[N],b[N];
ll dp[N];
map<int,int>val;
int main(){
ios_base::sync_with_stdio(0);
cin.tie(0),cout.tie(0);
int n;
cin>>n;
vector<int>v;
for(int i=1;i<=n;i++){
cin>>a[i]>>b[i];
for(int j=a[i];j<=b[i];j++){
v.pb(j);
}
}
sort(all(v));
val[v[0]]=1;
int cnt=0;
for(int i=1;i<sz(v);i++){
if(v[i]==v[i-1])continue;
val[v[i]]=val[v[i-1]]+1;
cnt=val[v[i]];
}
dp[0]=1;
for(int i=1;i<=n;i++){
ll sum=0;
int l=val[a[i]];
int r=val[b[i]];
for(int j=0;j<l;j++){
sum+=dp[j];
sum%=mod;
}
for(int j=l;j<=r;j++){
dp[j]+=sum;
dp[j]%=mod;
sum=dp[j];
}
}
ll ans=0;
for(int i=1;i<=cnt;i++){
ans+=dp[i];
ans%=mod;
}
cout<<ans;
}
