#include <bits/stdc++.h>
#define vi vector<int>
#define ve vector
#define ll long long
#define vf vector<float>
#define vll vector<pair<ll,ll>>
#define ii pair<int,int>
#define vvi vector<vi>
#define vii vector<ii>
#define gii greater<ii>
#define pb push_back
#define mp make_pair
#define fi first
#define se second
#define INF 1e9
#define eps 1e-7
#define eps1 1e-2
#define optimise ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
#define MAX_A 2e5+5
using namespace std;
const int MOD = 1e4+7;
const int nax = 1005;
const int nax2 = 200005;
typedef complex<int> Point;
#define X real()
#define Y imag()
int s[nax],e[nax];
vi adj[nax];
vi d;
int main(){
optimise;
int n,q;
cin >> n >> q;
for (int i = 0; i < n; ++i)
{
cin >> s[i] >> e[i];
}
for (int i = 0; i < n; ++i)
{
for (int j = 0; j < n; ++j)
{
if(i==j) continue;
if(e[i] <= e[j] && s[j] <= e[i]) adj[i].pb(j);
}
}
while(q--){
int s,e;
cin >> s >> e;
s--,e--;
int res = -1;
if(s == e)
{
cout << 0 << endl;
continue;
}
d.assign(n, INF);
d[s] = 0;
set<ii> q;
q.insert({0, s});
while (!q.empty()) {
int v = q.begin()->second;
q.erase(q.begin());
for (auto edge : adj[v]) {
int u = edge;
if (d[v] + 1 < d[u]) {
q.erase({d[u], u});
d[u] = d[v] + 1;
if(u == e) {
res = d[u];
break;
}
q.insert({d[u], u});
}
}
}
if(res == -1) cout << "impossible" << endl;
else cout << res << endl;
}
}
