/*input
8 5
1 2
3 4
1 5
6 7
5 10
10 20
15 20
999999999 1000000000
1 6
1 7
2 4
3 3
5 8
*/
#include <bits/stdc++.h>
using namespace std;
int main()
{
ios_base::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
int N, Q;
cin >> N >> Q;
pair<pair<int, int>, int>A[N];
for (int i = 0; i < N; i++)
{
cin >> A[i].first.second >> A[i].first.first;
A[i].second = i;
}
sort(A, A + N);
int p[N];
for (int i = 0; i < N; i++)
p[A[i].second] = i;
int S[N], E[N];
for (int i = 0; i < N; i++)
{
S[i] = A[i].first.second;
E[i] = A[i].first.first;
}
for (int i = 0; i < N; i++)
{
//S[i] = upper_bound(E, E + N, S[i]) - E;
}
int D[N][N];
for (int i = 0; i < N; i++)
for (int j = 0; j < N; j++)
D[i][j] = N + 10;
for (int i = N - 1; i >= 0; i--)
{
D[i][i] = 0;
for (int j = i + 1; j < N; j++)
{
if (S[j] <= E[i])
D[i][j] = 1;
else
{
for (int k = i + 1; k < j; k++)
D[i][j] = min(D[i][j], D[i][k] + D[k][j]);
}
}
}
while (Q--)
{
int s, t;
cin >> s >> t;
s = p[s - 1];
t = p[t - 1];
int k = D[s][t];
if (s == t)
{
cout << "0\n";
}
else {
if (S[t] <= E[s] && E[s] <= E[t])
cout << "1\n";
else {
if (k > N)
cout << "impossible\n";
else
cout << k << "\n";
}
}
}
}
