#include <bits/stdc++.h>
using namespace std;
const int MAX_N = 1e5 + 5;
const int INF = 1e9 + 7;
int S[MAX_N], E[MAX_N];
int pre[MAX_N][20];
pair <int, int> tree[8 * MAX_N];
void build(int idx, int l, int r) {
tree[idx] = make_pair(INF, INF);
if(l == r) {
return;
}
int mid = (l + r) / 2;
build(idx * 2, l, mid);
build(idx * 2 + 1, mid + 1, r);
}
void update(int idx, int l, int r, int q, pair <int, int> v) {
if(l == r) {
tree[idx] = min(tree[idx], v);
return;
}
int mid = (l + r) / 2;
if(q <= mid) {
update(idx * 2, l, mid, q, v);
}
else {
update(idx * 2 + 1, mid + 1, r, q, v);
}
tree[idx] = min(tree[idx * 2], tree[idx * 2 + 1]);
}
pair <int, int> query(int idx, int l, int r, int ql, int qr) {
if(r < ql or qr < l) {
return make_pair(INF, INF);
}
if(ql <= l and r <= qr) {
return tree[idx];
}
int mid = (l + r) / 2;
return min(query(idx * 2, l, mid, ql, qr), query(idx * 2 + 1, mid + 1, r, ql, qr));
}
int main() {
cin.tie(nullptr)->sync_with_stdio(false);
int N, M, Q;
cin >> N >> Q;
vector <int> vec;
for(int i = 1; i <= N; i++) {
cin >> S[i] >> E[i];
vec.push_back(S[i]);
vec.push_back(E[i]);
}
sort(vec.begin(), vec.end());
vec.resize(unique(vec.begin(), vec.end()) - vec.begin());
M = vec.size();
for(int i = 1; i <= N; i++) {
S[i] = lower_bound(vec.begin(), vec.end(), S[i]) - vec.begin() + 1;
E[i] = lower_bound(vec.begin(), vec.end(), E[i]) - vec.begin() + 1;
}
build(1, 1, M);
for(int i = 1; i <= N; i++) {
update(1, 1, M, E[i], make_pair(S[i], i));
}
for(int i = 1; i <= N; i++) {
auto [lm, nxt] = query(1, 1, M, S[i], E[i]);
if(nxt != i and lm != S[i]) {
pre[i][0] = nxt;
}
}
for(int j = 1; j < 20; j++) {
for(int i = 1; i <= N; i++) {
pre[i][j] = pre[pre[i][j - 1]][j - 1];
}
}
while(Q--) {
int s, e;
cin >> s >> e;
if(s == e) {
cout << "0\n";
}
else if(E[s] > E[e]) {
cout << "impossible\n";
}
else if(S[e] <= E[s] and E[s] <= E[e]) {
cout << "1\n";
}
else {
int ans = 2;
for(int i = 19; i >= 0; i--) {
if(pre[e][i] != 0 and E[s] < S[pre[e][i]]) {
e = pre[e][i];
ans += (1<<i);
}
}
if(pre[e][0] != 0 and S[pre[e][0]] <= E[s]) {
cout << ans << '\n';
}
else {
cout << "impossible\n";
}
}
}
return 0;
}
