#include <bits/stdc++.h>
using namespace std;
const int N = 1e5;
int n, q;
pair<int, int> sg[N];
signed main() {
ios::sync_with_stdio(false); cin.tie(nullptr);
cin >> n >> q;
for (int i = 0; i < n; i++) {
int l, r;
cin >> l >> r;
sg[i] = make_pair(l, r);
}
for (int i = 0; i < q; i++) {
int x, y;
cin >> x >> y;
x--; y--;
int z = -1;
vector<bool> vis(n, 0);
queue<pair<int, int>> qu;
qu.push(make_pair(0, x));
while (!qu.empty()) {
int d = qu.front().first;
int u = qu.front().second;
qu.pop();
if (vis[u]) continue;
vis[u] = 1;
if (u == y) {
z = d;
break;
}
for (int i = 0; i < n; i++) {
if (vis[i]) continue;
if (sg[i].first <= sg[u].second && sg[u].second <= sg[i].second) {
qu.push(make_pair(d+1, i));
}
}
}
if (z == -1) cout << "impossible\n";
else cout << z << "\n";
}
}
