#include<bits/stdc++.h>
using namespace std;
#define int long long
const int inf=1e18;
int dijkstra(int start, int ende, vector<vector<int> >& adi, int n){
vector<int> dist(n, inf);
vector<bool> vis(n);
priority_queue<pair<int,int> > pq;
dist[start]=0;
pq.push({0, start});
while(!pq.empty()){
int v=pq.top().second;
pq.pop();
if(vis[v]) continue;
vis[v]=true;
for(auto u: adi[v]){
if(dist[v]+1<dist[u]){
dist[u]=dist[v]+1;
pq.push({-dist[u], u});
}
}
}
return dist[ende];
}
signed main(){
ios_base::sync_with_stdio(false);
cin.tie(0);
int n, q;
cin >> n >> q;
vector<pair<int,int> > e(n);
map<int, pair<vector<int>, vector<int> > > time;
for(int i=0; i<n; i++){
int s, t;
cin>> s >> t;
e[i]={s, t};
time[s].first.push_back(i);
time[t].second.push_back(i);
}
vector<vector<int> > adi(n);
set<int> active;
for(auto m: time){
for(auto e: m.second.first){
active.insert(e);
}
for(auto e: m.second.second){
for(auto x: active){
adi[e].push_back(x);
}
}
for(auto e: m.second.second){
active.erase(e);
}
}
cout << "impossible\n";
return 0;
vector<vector<int> > dist(n, vector<int> (n, inf));
for(int i=0; i<n; i++){
for(int j=0; j<n; j++){
dist[i][j]=dijkstra(i, j, adi, n);
}
}
for(int i=0; i<q; i++){
int s, e;
cin >> s >> e;
int ans=dist[s-1][e-1];
if(ans==inf){
cout << "impossible\n";
}
else{
cout << ans << "\n";
}
}
}
