#include "bits/stdc++.h"
using namespace std;
const int N = 1e6 + 10;
int l[N], r[N], n, q;
vector<int> events[N];
vector<int> go(int start) {
queue<int> q;
vector<bool> closed(n, false);
q.push(start);
vector<int> dist(n, -1);
dist[start] = 0;
for(int i = r[start]; i >= 0; --i) {
while(!q.empty() && closed[q.front()]) q.pop();
for(int e: events[i]) {
if(e == start) continue;
if(e < 0) continue;
if(!q.empty()) {
dist[e] = dist[q.front()] + 1;
q.push(e);
}
}
for(int e: events[i]) {
if(e >= 0) continue;
int idx = -e - 1;
closed[idx] = true;
}
}
return dist;
}
int main() {
vector<int> v;
cin >> n >> q;
for(int i = 0; i < n; ++i) {
cin >> l[i] >> r[i];
v.push_back(l[i]);
v.push_back(r[i]);
}
sort(v.begin(), v.end());
v.erase(unique(v.begin(), v.end()), v.end());
for(int i = 0; i < n; ++i) {
l[i] = lower_bound(v.begin(), v.end(), l[i]) - v.begin();
r[i] = lower_bound(v.begin(), v.end(), r[i]) - v.begin();
events[r[i]].push_back(i);
events[l[i]].push_back(-i - 1);
}
if(n <= 5000) {
vector<vector<int>> dist;
for(int i = 0; i < n; ++i) dist.push_back(go(i));
while(q--) {
int a, b; cin >> a >> b; --a, --b;
if(dist[b][a] == -1) cout << "impossible\n";
else cout << dist[b][a] << "\n";
}
} else {
while(q--) {
int a, b; cin >> a >> b; --a, --b;
vector<int> dist = go(b);
if(dist[a] == -1) cout << "impossible\n";
else cout << dist[a] << "\n";
}
}
}
