#include <bits/stdc++.h>
using namespace std;
#define InTheNameOfGod ios::sync_with_stdio(0);cin.tie(0); cout.tie(0);
using ll = long long;
const int maxN = 2e5 + 5;
const int MOD = 1e9 + 7;
const int INF = 1e9 + 7;
vector<vector<int> > g;
vector<vector<int> > dist;
vector<pair<int, int>> pos;
struct Event {
int s,e, ind;
};
bool operator<(Event &a, Event &b) {
if(a.s == b.s) return a.e < b.e;
return a.s < b.s;
}
int main() {
/*#ifndef ONLINE_JUDGE
freopen("../../input.txt", "r", stdin);
freopen("../../output.txt", "w", stdout);
#endif*/
InTheNameOfGod;
int n,q;
cin >> n >> q;
g.resize(n+1);
dist.resize(n+1, vector<int>(n+1, -1));
vector<Event > v;
for(int i = 0; i < n; i++) {
int x,y;
cin >> x >> y;
v.push_back({x, y, i+1});
}
for(int i = 0; i < n; i++) {
for(int j = 0; j < n; j++) {
if(i == j) continue;
if(v[i].e >= v[j].s && v[i].e <= v[j].e) {
g[i+1].push_back(j+1);
}
}
}
for(int i = 1; i <= n; i++) {
queue<int> q;
q.push(i);
dist[i][i] = 0;
while(!q.empty()) {
int cur = q.front();
q.pop();
for(int sz : g[cur]) {
if(dist[i][sz] != -1) continue;
dist[i][sz] = dist[i][cur] + 1;
q.push(sz);
}
}
}
while(q--) {
int x,y;
cin >> x >> y;
if(dist[x][y] == -1) cout << "impossible\n";
else cout << dist[x][y] << "\n";
}
return 0;
}
