#include<bits/stdc++.h>
using namespace std;
signed main() {
ios :: sync_with_stdio(0);
cin.tie(0); cout.tie(0);
#define endl "\n"
int n,q;
cin >> n >> q;
vector <int> s(n+1,-1),e(n+1,-1);
for (int i = 1; i <= n; i++) {
cin >> s[i] >> e[i];
}
vector <pair<int,int>> t(4*n+5,{-1,-1});
vector <pair<int,int>> lazy(4*n+5,{-1,-1});
auto applay = [&](int node, pair<int,int> val) {
lazy[node] = max(lazy[node],val);
t[node] = max(t[node],val);
};
auto push = [&](int node) {
if (lazy[node] != make_pair(-1,-1)) {
applay(node*2,lazy[node]);
applay(node*2+1,lazy[node]);
lazy[node] = {-1,-1};
}
};
function<void(int,int,int,int,int,pair<int,int>)> update = [&](int node, int l, int r, int L, int R, pair<int,int> val) {
if (l > R || r < L) return;
if (L <= l && r <= R) {
applay(node,val);
return;
}
push(node);
int mid = (l+r)/2;
update(node*2,l,mid,L,R,val);
update(node*2+1,mid+1,r,L,R,val);
t[node] = max(t[node*2],t[node*2+1]);
};
function <pair<int,int>(int,int,int,int)> getmax = [&](int node, int l, int r, int pos) {
if (pos > r || pos < l) return make_pair(-1,-1);
if (l == r) return t[node];
push(node);
int mid = (l+r)/2;
return max(getmax(node*2,l,mid,pos),getmax(node*2+1,mid+1,r,pos));
};
vector <pair<int,int>> r;
for (int i = 1; i <= n; i++) {
r.emplace_back(e[i],i);
}
sort(r.begin(),r.end());
for (int i = 0; i < n; i++) {
int l = lower_bound(r.begin(),r.end(),make_pair(s[r[i].second],-1)) - r.begin();
update(1,0,n,l,n-1,r[i]);
}
vector <vector<pair<int,int>>> up(n+1,vector<pair<int,int>>(20,{-1,-1}));
for (int i = 0; i < n; i++) {
pair<int, int> res = getmax(1, 0, n, i);
if (res.second != -1 && res.first > r[i].first) {
up[r[i].second][0] = res;
} else {
up[r[i].second][0] = {-1, -1};
}
}
for (int i = 1; i <= 19; i++) {
for (int j = 1; j <= n; j++) {
if (up[j][i-1].second == -1) continue;
up[j][i] = up[up[j][i-1].second][i-1];
}
}
while (q--) {
int S,E;
cin >> S >> E;
if (s[S] > e[E]) {
cout << "impossible" << endl;
continue;
}
if (S == E) {
cout << 0 << endl;
continue;
}
int cur = 0;
if (s[E] <= e[S] && e[S] <= e[E]) {
cout << cur+1 << endl;
continue;
}
for (int i = 19; i >= 0; i--) {
if (up[S][i] == make_pair(-1,-1)) continue;
if (up[S][i].first < s[E]) {
cur += (1<<i);
S = up[S][i].second;
}
}
if (s[E] <= e[S] && e[S] <= e[E]) {
cout << cur+1 << endl;
continue;
}
cur++;
S = up[S][0].second;
if (s[E] <= e[S] && e[S] <= e[E]) {
cout << cur+1 << endl;
continue;
}
cout << "impossible" << endl;
}
}
