#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef vector<ll> v;
typedef vector<v> vv;
typedef vector<vv> vvv;
typedef pair<ll, ll> p;
typedef vector<p> vp;
typedef vector<vp> vvp;
typedef vector<vvp> vvvp;
typedef pair<ll, p> tri;
typedef vector<tri> vtri;
typedef vector<vtri> vvtri;
typedef vector<vvtri> vvvtri;
typedef vector<bool> vb;
typedef vector<vb> vvb;
typedef vector<vvb> vvvb;
#define f first
#define s second
#define pb push_back
#define eb emplace_back
#define all(v) (v).begin(),(v).end()
const ll INF = 1e18;
const ll mod = 1e9 + 7;
ll query(vp &st, ll l, ll r)
{
l += st.size() / 2;
r += st.size() / 2;
ll bestIndex, best = INF;
while (l <= r)
{
if (l % 2 == 1)
{
if (st[l].f < best)
{
best = st[l].f;
bestIndex = st[l].s;
}
l++;
}
if (r % 2 == 0)
{
if (st[r].f < best)
{
best = st[r].f;
bestIndex = st[r].s;
}
r--;
}
l /= 2; r /= 2;
}
return bestIndex;
}
int main()
{
ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);
ll N, Q;
cin >> N >> Q;
vp events(N);
for (ll i = 0; i < N; i++) cin >> events[i].f >> events[i].s;
v numbers;
for (ll i = 0; i < N; i++)
{
numbers.pb(events[i].f);
numbers.pb(events[i].s);
}
sort(all(numbers)); numbers.erase(unique(all(numbers)),numbers.end());
map<ll, ll> shrink;
for (ll i = 0; i < numbers.size(); i++) shrink[numbers[i]] = i;
for (ll i = 0; i < N; i++)
{
events[i].f = shrink[events[i].f];
events[i].s = shrink[events[i].s];
}
ll m = numbers.size();
ll n = pow(2, ceil(log2(m)));
vp st(2 * n, p(INF, -1));
for (ll i = 0; i < N; i++) if (events[i].f < st[n + events[i].s].f) st[n + events[i].s] = p(events[i].f, i);
for (ll i = n - 1; i > 0; i--)
{
if (st[2 * i].f < st[2 * i + 1].f) st[i] = st[2 * i];
else st[i] = st[2 * i + 1];
}
v prev(N);
for (ll curEvent = 0; curEvent < N; curEvent++)
{
ll bestEvent = query(st, events[curEvent].f, events[curEvent].s);
//TODO check if worse than curEvent
prev[curEvent] = bestEvent;
}
ll logN = log2(N);
vv prevLifting(N, v(logN + 1, -1));
for (ll i = 0; i < N; i++) prevLifting[i][0] = prev[i];
for (ll j = 1; j <= logN; j++)
{
for (ll i = 0; i < N; i++)
{
prevLifting[i][j] = prevLifting[prevLifting[i][j - 1]][j - 1];
}
}
while (Q--)
{
ll s, e;
cin >> s >> e; s--; e--;
if (s == e)
{
cout << "0\n";
continue;
}
if (events[s].s > events[e].s)
{
cout << "impossible\n";
continue;
}
if (events[e].f <= events[s].s && events[e].s >= events[s].s)
{
cout << "1\n";
continue;
}
ll curEvent = e;
ll hops = 0;
for (ll j = logN; j >= 0; j--)
{
ll next = prevLifting[curEvent][j];
if (events[s].s < events[next].f)
{
curEvent = next;
hops += (1 << j);
}
}
curEvent = prev[curEvent]; hops++;
if (events[s].s >= events[curEvent].f)
{
cout << hops + 1 << "\n";
continue;
}
cout << "impossible\n";
}
return 0;
}
