#include <bits/stdc++.h>
using namespace std;
const int N = 1e5 + 10;
int n,q,s[N],e[N],d[N];
bool o[N];
vector<int> g[N];
void bfs(int v){
for(int i = 1; i <= n; ++i) d[i] = N, o[i] = 0;
d[v] = 0;
queue<int> q;
q.push(v);
while(!q.empty()){
int r = q.front();
q.pop();
for(auto u : g[r]){
if(!o[u]){
o[u] = 1, d[u] = d[r]+1;
q.push(u);
}
}
}
}
int main(){
ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
cin >> n >> q;
for(int i = 1; i <= n; ++i) cin >> s[i] >> e[i];
if(n <= 5000){
for(int i = 1; i <= n; ++i){
for(int j = 1; j <= n; ++j){
if(i == j) continue;
if(s[j] <= e[i] && e[i] <= e[j]){
// cout << i << " " << j << "\n";
g[i].push_back(j);
}
}
}
while(q--){
int w,z; cin >> w >> z;
bfs(w);
if(d[z] == N){
cout << "impossible\n";
}else{
cout << d[z] << "\n";
}
}
}
return 0;
}
