/*#pragma GCC optimize("O3")
#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#pragma GCC target ("avx2")
*/
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define fix fixed<<setprecision
#define forn(i, n) for(int i = 1; i <= (n); ++i)
#define all(v) v.begin(),v.end()
#define rall(v) v.rbegin(), v.rend()
#define sz(s) (int) (s).size()
#define pb push_back
#define pf push_front
#define popb pop_back
#define popf pop_front
#define ss second
#define ff first
using namespace std;
using namespace __gnu_pbds;
using pii = pair<int,int>;
using pll = pair<long long, long long>;
using ll = long long;
using ull = unsigned long long;
template<typename T> using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
const int N = 5e3+100, inf = 1e9+7;
int n, q, s[N], e[N], d[N][N];
vector<int> g[N];
int main(){
//freopen("cownomics.in", "r", stdin);
//freopen("cownomics.out", "w", stdout);
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];
for(int i = 1; i <= n; ++i)
for(int j = 1; j <= n; ++j)
if(i != j && s[j] <= e[i] && e[i] <= e[j])
g[i].pb(j);
for(int v = 1; v <= n; ++v){
for(int u = 1; u <= n; ++u)
d[v][u] = inf;
d[v][v] = 0;
queue<int> q;
q.push(v);
while(!q.empty()){
int i = q.front();
q.pop();
for(auto to : g[i])
if(d[v][to] == inf){
d[v][to] = d[v][i] + 1;
q.push(to);
}
}
}
while(q--){
int a, b;
cin >> a >> b;
if(d[a][b] == inf)
cout << "impossible\n";
else
cout << d[a][b] << '\n';
}
}
