/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//#pragma GCC optimize("O3,unroll-loops")
//#pragma GCC target("avx,avx2,fma")
#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define ull unsigned long long
#define ld long double
#define ui unsigned int
#define f first
#define s second
#define ins insert
#define pb push_back
#define mp make_pair
#define ln '\n'
#define int ll
#define pii pair<int , int>
#define INF LLONG_MAX
#define vv(a) vector<a>
#define pp(a, b) pair<a, b>
#define pq(a) priority_queue<a>
#define qq(a) queue<a>
#define ss(a) set<a>
#define mss(a) multiset<a>
#define mm(a, b) map<a, b>
#define mmm(a , b) multimap<a , b>
#define sz(x) (x).size()
#define all(x) (x).begin() , (x).end()
#define fastio \
ios_base::sync_with_stdio(0); \
cin.tie(0); \
cout.tie(0);
/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
const int MAX = 5010;
vv(pii) a(MAX);
vv(vv(int)) g(MAX);
vv(vv(int)) dist(MAX , vv(int) (MAX , -1));
void BFS(int node){
dist[node][node] = 0;
queue<int> Q;
Q.push(node);
while(!Q.empty()){
int from = Q.front();
Q.pop();
for(auto to : g[from]){
if(dist[node][to] == -1){
dist[node][to] = dist[node][from] + 1;
Q.push(to);
}
}
}
}
void solve(){
int n , q;
cin >> n >> q;
for(int i=0 ; i<n ; i++){
cin >> a[i].f >> a[i].s;
}
for(int i=0 ; i<n ; i++){
for(int j=0 ; j<n ; j++){
if(i != j){
if(a[j].f <= a[i].s && a[j].s >= a[i].s){
g[i].pb(j);
}
}
}
}
for(int i=0 ; i<n ; i++){
BFS(i);
}
//cout << dist[0][3] << ln;
for(int i=0 ; i<q ; i++){
int u , v;
cin >> u >> v;
u--; v--;
if(dist[u][v] == -1){
cout << "impossible" << ln;
}
else{
cout << dist[u][v] << ln;
}
}
}
signed main(){
fastio
int t = 1;
//cin >> t;
while(t--){
solve();
}
return 0;
}
