// Be name khoda //
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define all(x) x.begin(), x.end()
#define pb push_back
#define fi first
#define se second
#define mp make_pair
const int maxn5 = 2e5 + 10;
const int lg = 19;
vector <int> ch, av, req[maxn5];
int l[maxn5], r[maxn5], ans[maxn5], par[lg][maxn5];
int x[maxn5], y[maxn5], ind[maxn5], per[maxn5];
pair <int, int> fen[maxn5];
inline bool cmp(int i, int j){return r[i] < r[j] || (r[i] == r[j] && l[i] < l[j]);}
inline void max_mos(int id, pair <int, int> val){
for(++id; id < maxn5; id += id & -id){
fen[id] = max(fen[id], val);
ch.pb(id);
}
}
inline pair <int, int> get_max(int id){
pair <int, int> ret = {-1, -1};
for(++id; id; id -= id & -id)
ret = max(ret, fen[id]);
return ret;
}
inline void fen_reset(){
for(auto u : ch)
fen[u] = {-1, -1};
ch.clear();
}
void solve(int lq, int rq){
if(rq - lq == 1)
return;
int mid = (lq + rq) >> 1;
solve(lq, mid);
int mn = l[per[mid]];
for(int i = mid; i < rq; i++){
mn = min(mn, l[per[i]]);
max_mos(l[per[i]], mp(r[per[i]], i));
for(auto id : req[i]) if(x[id] >= lq && x[id] < mid){
int v = x[id];
if(r[per[v]] < mn){
for(int j = lg - 1; j >= 0; j--) if(par[j][v] != -1 && r[per[par[j][v]]] < mn){
v = par[j][v];
ans[id] += (1 << j);
}
v = par[0][v];
ans[id]++;
}
if(v == -1){
ans[id] = -1;
continue;
}
//cout << "hey it's " << i << ' ' << id << ' ' << x[id] << ' ' << v << '\n';
auto mx = get_max(r[per[v]]);
x[id] = mx.se;
ans[id]++;
}
}
for(int i = mid - 1; i >= lq; i--){
for(int j = 0; j < lg; j++)
par[j][i] = -1;
par[0][i] = get_max(r[per[i]]).se;
max_mos(l[per[i]], mp(r[per[i]], i));
}
fen_reset();
solve(mid, rq);
for(int i = 1; i < lg; i++) for(int v = lq; v < mid; v++)
if(par[i - 1][v] != -1) par[i][v] = par[i - 1][par[i - 1][v]];
}
int main(){
ios_base::sync_with_stdio(false); cin.tie(0);
fill(fen, fen + maxn5, mp(-1, -1));
int n, q; cin >> n >> q;
for(int i = 0; i < n; i++){
cin >> l[i] >> r[i];
av.pb(l[i]);
av.pb(r[i]);
per[i] = i;
}
sort(all(av));
av.resize(unique(all(av)) - av.begin());
for(int i = 0; i < n; i++){
l[i] = lower_bound(all(av), l[i]) - av.begin();
r[i] = lower_bound(all(av), r[i]) - av.begin();
//cout << i << ' ' << l[i] << ' ' << r[i] << '\n';
}
sort(per, per + n, cmp);
for(int i = 0; i < n; i++)
ind[per[i]] = i;
for(int i = 0; i < q; i++){
cin >> x[i] >> y[i];
x[i]--; y[i]--;
if(x[i] == y[i])
continue;
if(ind[x[i]] > ind[y[i]])
ans[i] = r[y[i]] == r[x[i]] ? 1 : -1;
else{
req[ind[y[i]]].pb(i);
x[i] = ind[x[i]];
y[i] = ind[y[i]];
}
//cout << "ok " << i << ' ' << x[i] << ' ' << y[i] << '\n';
}
memset(par, -1, sizeof par);
solve(0, n);
for(int i = 0; i < q; i++){
if(ans[i] == -1)
cout << "impossible\n";
else
cout << ans[i] << '\n';
}
}
/*
5 1
1 3
2 4
4 7
7 9
3 7
1 4
3 2
*/
