#include <bits/stdc++.h>
using namespace std;
const int N = int(1e5) + 9;
vector<int> g[N];
int main() {
ios::sync_with_stdio(false);
cin.tie(0);
int n, q;
cin >> n >> q;
vector<int> s(n), e(n);
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 && s[j] <= e[i] && e[i] <= e[j]) {
g[i].push_back(j);
}
}
}
vector dist(n, vector<int>(n, -1));
for (int i = 0; i < n; i++) {
dist[i][i] = 0;
vector<int> que(1, i);
vector<int> vis(n);
vis[i] = 1;
for (int it = 0; it < int(que.size()); it++) {
int u = que[it];
for (int v : g[u]) {
if (dist[i][v] == -1) {
dist[i][v] = dist[i][u] + 1;
que.push_back(v);
}
}
}
}
while (q--) {
int x, y;
cin >> x >> y;
--x, --y;
if (dist[x][y] == -1) {
cout << "impossible" << '\n';
} else {
cout << dist[x][y] << '\n';
}
}
return 0;
}
