#include <bits/stdc++.h>
using namespace std;
const int N = 1e5 + 10, LG = 18;
int n, que, par[N][LG], a[N][2], dist[5005][5005];
vector<pair<pair<int, int>, int>> vec;
vector<int> g[N];
int main(){
ios::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
cin >> n >> que;
for (int i = 0; i < n; i ++){
int s, e;
cin >> s >> e;
a[i][0] = s, a[i][1] = e;
// vec.push_back({{s, 0}, i});
// vec.push_back({{e, 1}, i});
}
// sort(vec.begin(), vec.end());
for (int i = 0; i < n; i ++){
for (int j = 0; j < n; j ++){
if (i == j) continue;
if (a[i][0] <= a[j][1] and a[j][1] <= a[i][1])
g[j].push_back(i);
}
}
queue<int> q;
for (int s = 0; s < n; s ++){
for (int j = 0; j < n; j ++)
dist[s][j] = 1e9;
dist[s][s] = 0;
q.push(s);
while (!q.empty()){
int v = q.front();
q.pop();
for (int u : g[v]){
if (dist[s][u] > dist[s][v] + 1){
dist[s][u] = dist[s][v] + 1;
q.push(u);
}
}
}
}
for (int id = 0; id < que; id ++){
int l, r;
cin >> l >> r;
l--; r--;
if (dist[l][r] > 1e8)
cout << "impossible\n";
else
cout << dist[l][r] << '\n';
continue;
if (a[r][1] < a[l][1]){
cout << "impossible\n";
continue;
}
if (a[r][1] == a[l][1]){
cout << 1 - (l == r) << '\n';
continue;
}
int cur = l, ans = 0;
set<pair<int, int>> st;
for (auto P : vec){
auto [E, i] = P;
if (cur == r)
break;
if (!E.second)
st.insert({a[i][1], i});
else{
st.erase({a[i][1], i});
if (i != cur) continue;
if (st.empty()){
ans = -1;
break;
}
else{
auto it = st.upper_bound({a[r][1], r});
if (it == st.begin()){
ans = -1;
break;
}
it--;
cur = (*it).second;
ans++;
}
}
}
if (ans == -1){
cout << "impossible\n";
continue;
}
cout << ans << endl;
}
return 0;
set<pair<int, int>> st;
for (auto P : vec){
auto [E, i] = P;
if (!E.second)
st.insert({a[i][1], i});
else{
st.erase({a[i][1], i});
if (st.empty())
par[i][0] = -1;
else{
auto R = *st.rbegin();
par[i][0] = R.second;
}
}
}
for (int j = 1; j < LG; j ++)
for (int i = 0; i < n; i ++)
if (par[i][j - 1] != -1)
par[i][j] = par[par[i][j - 1]][j - 1];
for (int i = 0; i < que; i ++){
int l, r;
cin >> l >> r;
l--, r--;
if (a[r][1] < a[l][1]){
cout << "impossible\n";
continue;
}
if (a[r][1] == a[l][1]){
cout << 1 - (l == r) << '\n';
continue;
}
int cur = l, ans = 0;
for (int j = LG - 1; j >= 0; j --){
if (par[cur][j] == -1) continue;
if (a[par[cur][j]][1] < a[r][1])
cur = par[cur][j], ans += (1 << j);
}
if (par[cur][0] == -1){
cout << "impossible\n";
continue;
}
if (a[cur][1] >= a[r][0]){
cout << ans + 1 << '\n';
continue;
}
if (a[cur][1] < a[r][0]){
cout << "impossible\n";
continue;
}
cout << ans + 1 << '\n';
}
}
