#include <bits/stdc++.h>
using namespace std;
struct RMQ {
int n;
vector<pair<int, int>> tree;
RMQ(int n) {
this->n = n;
tree = vector<pair<int, int>>(4 * n + 1, {1e9 + 1, -1});
}
void update(int i, int l, int r, int qp, pair<int, int> val) {
if (l == r) {
tree[i] = min(tree[i], val);
return;
}
int m = (l + r) / 2;
if (qp <= m) {
update(i * 2, l, m, qp, val);
} else {
update(i * 2 + 1, m + 1, r, qp, val);
}
tree[i] = min(tree[i * 2], tree[i * 2 + 1]);
}
void update(int qp, pair<int, int> val) {
update(1, 0, n - 1, qp, val);
}
pair<int, int> query(int i, int l, int r, int ql, int qr) {
if (l > qr || ql > r) {
return {1e9 + 1, -1};
}
if (ql <= l && r <= qr) {
return tree[i];
}
int m = (l + r) / 2;
return min(query(i * 2, l, m, ql, qr),
query(i * 2 + 1, m + 1, r, ql, qr));
}
pair<int, int> query(int ql, int qr) {
return query(1, 0, n - 1, ql, qr);
}
};
int main() {
int n, q;
cin >> n >> q;
vector<int> pool;
vector<int> s(n), e(n);
RMQ seg(n * 2);
for (int i = 0; i < n; ++i) {
cin >> s[i] >> e[i];
pool.push_back(e[i]);
pool.push_back(s[i]);
}
sort(begin(pool), end(pool));
pool.erase(unique(begin(pool), end(pool)), end(pool));
for (int i = 0; i < n; ++i) {
int r = lower_bound(begin(pool), end(pool), e[i]) - begin(pool);
seg.update(r, {s[i], i});
}
vector<vector<int>> lift(n, vector<int>(20, -1));
for (int i = 0; i < n; ++i) {
int r = lower_bound(begin(pool), end(pool), e[i]) - begin(pool);
int l = lower_bound(begin(pool), end(pool), s[i]) - begin(pool);
auto p = seg.query(l, r);
lift[i][0] = p.second;
}
for (int j = 1; j < 20; ++j) {
for (int i = 0; i < n; ++i) {
if (lift[i][j - 1] == -1) continue;
lift[i][j] = lift[lift[i][j - 1]][j - 1];
}
}
while (q--) {
int x, y;
cin >> x >> y;
--x; --y;
if (x == y) {
cout << "0\n";
continue;
}
if (s[y] <= e[x] && e[x] <= e[y]) {
cout << "1\n";
continue;
}
int steps = 2;
// cout << x << " " << y << " => ";
// cout << "X = " << s[x] << " , " << e[x] << endl;
// cout << "Y = " << s[y] << " , " << e[y] << endl;
for (int j = 19; j >= 0; --j) {
if (lift[y][j] == -1) {
continue;
}
int ny = lift[y][j];
// cout << ny << "\n";
// cout << "CAND = " << s[ny] << " " << e[ny] << endl;
if (e[x] < s[ny]) {
y = ny;
steps += (1 << j);
}
}
y = lift[y][0];
// cout << x << " " << y << endl;
if (y == -1) {
cout << "impossible\n";
continue;
}
// cout << "X = " << s[x] << " , " << e[x] << endl;
// cout << "Y = " << s[y] << " , " << e[y] << endl;
if (e[x] < s[y] || e[x] > e[y]) {
cout << "impossible\n";
continue;
}
cout << steps << "\n";
}
}
