#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<ll, ll> pll;
typedef pair<int, int> pii;
typedef vector<int> vi;
typedef vector<ll> vll;
const ll mod=1e9+7;
const ll maxn=1e5+5;
const int INF=1e8;
#define ok ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
#define fi first
#define se second
#define pb push_back
#define ub upper_bound
#define lb lower_bound
#define endl '\n'
vi adj[maxn];
int n, q, dis[5001][5001], u, v;
pii arr[maxn];
int main() {
ok
cin >> n >> q;
for(int i=1; i<=n; i++) cin >> arr[i].fi >> arr[i].se;
if(n<=5000) {
for(int i=1; i<=n; i++) {
for(int j=1; j<=n; j++) {
if(i==j) continue;
if(arr[i].se>=arr[j].fi && arr[i].se<=arr[j].se) adj[i].pb(j);
}
}
memset(dis, -1, sizeof dis);
for(int i=1; i<=n; i++) {
dis[i][i]=0;
queue<int> qu;
qu.push(i);
while(!qu.empty()) {
int fr=qu.front(); qu.pop();
for(auto it : adj[fr]) {
if(dis[i][it]==-1) {
dis[i][it]=dis[i][fr]+1;
qu.push(it);
}
}
}
}
while(q--) {
cin >> u >> v;
if(dis[u][v]==-1) cout << "impossible";
else cout << dis[u][v];
cout << endl;
}
}
}
