#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
const int MAX = 2e6 + 15;
const int INF = 0x3f3f3f3f;
const int MOD = 1e9 + 7;
#define pb push_back
#define sz(x) (int) x.size()
#define fr first
#define sc second
#define mp make_pair
#define all(x) x.begin(), x.end()
#define dbg(x) cout << #x << ": " << "[ " << x << " ]\n"
int n, q, h[MAX];
vector<int> adj[MAX];
struct event{
int s, e;
} ev[MAX];
bool f(event a, event b){ //can i do a --> b ?
return b.s <= a.e && a.e <= b.e;
}
int main(){
ios_base::sync_with_stdio(false);
cin.tie(NULL);
cin >> n >> q;
for(int i = 1; i <= n; i++){
cin >> ev[i].s >> ev[i].e;
}
for(int i = 1; i <= n; i++){
for(int j = 1; j <= n; j++){
if(i == j) continue;
if(f(ev[i], ev[j])) adj[i].pb(j);
}
}
while(q--){
int s, e; cin >> s >> e;
queue<int> q;
vector<int> dist(n + 1, -1);
q.push(s); dist[s] = 0;
while(q.size()){
int u = q.front();
q.pop();
for(auto v : adj[u]){
if(dist[v] == -1){
dist[v] = dist[u] + 1;
q.push(v);
}
}
}
if(dist[e] == -1) cout << "impossible" << '\n';
else cout << dist[e] << '\n';
}
return 0;
}
