#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
typedef long long ll;
using namespace __gnu_pbds;
using namespace std;
template <typename T>
using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
int main() {
ios_base::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
int n, q;
cin >> n >> q;
ll inf = 1e9;
vector<vector<int>> ans(n, vector<int>(n, inf));
vector<pair<int, int>> seg(n);
for(int i=0; i<n; ++i) cin >> seg[i].first >> seg[i].second;
queue<int> Q;
for(int s=0; s<n; ++s) {
ans[s][s] = 0;
Q.push(s);
while(Q.size()) {
int v = Q.front(); Q.pop();
for(int j=0; j<n; ++j) {
if(seg[j].first <= seg[v].second && seg[v].second <= seg[j].second) {
if(ans[s][j] == inf) {
ans[s][j] = ans[s][v] + 1;
Q.push(j);
}
}
}
}
}
while(q--) {
int a, b;
cin >> a >> b;
--a;--b;
if(ans[a][b]==inf) cout << "impossible\n";
else cout << ans[a][b] << "\n";
}
return 0;
}
