#include <bits/stdc++.h>
// #define int long long
#define pii pair<int, int>
#define ff first
#define ss second
using ll = long long;
using namespace std;
const ll mod = 998244353;
// const int inf = 1e18;
const int maxn = 1 << 21;
void solve()
{
int n, q;
cin >> n >> q;
vector<pii> segs(n);
for (auto &x : segs)
cin >> x.ff >> x.ss;
vector<int> cs;
for (auto x : segs)
cs.push_back(x.ff), cs.push_back(x.ss);
sort(cs.begin(), cs.end());
cs.resize(unique(cs.begin(), cs.end()) - cs.begin());
for (auto &x : segs)
x.ff = lower_bound(cs.begin(), cs.end(), x.ff) - cs.begin(),
x.ss = lower_bound(cs.begin(), cs.end(), x.ss) - cs.begin();
int k = cs.size();
vector<vector<int>> add(k);
for (auto &x : segs)
add[x.ff].push_back(x.ss);
for (auto &v : add)
if (v.size())
sort(v.begin(), v.end());
if (q > 100)
{
vector<vector<int>> prec(n);
for (int b = 0; b < n; b++)
{
int e = segs[b].ss;
vector<int> jmp(e + 2, -1);
int total = -1;
for (int i = 0; i < e; i++)
{
for (int x : add[i])
{
if (x <= e)
total = max(total, x);
if (i == segs[b].ff)
total = e + 1;
}
if (total >= i)
jmp[i] = total;
}
vector<int> dp(e + 2, -1);
dp[e + 1] = 0;
dp[e] = 1;
for (int i = e - 1; i >= 0; i--)
if (jmp[i] >= 0 && dp[jmp[i]] >= 0)
dp[i] = 1 + dp[jmp[i]];
prec[b] = dp;
}
while(q--)
{
int a,b;
cin >> a >> b;
if (segs[--a].ss > segs[--b].ss)
{
cout << "impossible\n";
continue;
}
if (a==b)
{
cout << "0\n";continue;
}
if (prec[b][segs[a].ss] < 0)
cout << "impossible\n";
else
cout << prec[b][segs[a].ss] << '\n';
}
return;
}
while (q--)
{
int a, b;
cin >> a >> b;
if (a == b)
{
cout << "0\n";
continue;
}
if (segs[--a].ss > segs[--b].ss)
{
cout << "impossible\n";
continue;
}
int e = segs[b].ss;
vector<int> jmp(e + 2, -1);
int total = -1;
for (int i = 0; i < e; i++)
{
for (int x : add[i])
{
if (x <= e)
total = max(total, x);
if (i == segs[b].ff)
total = e + 1;
}
if (total >= i)
jmp[i] = total;
}
vector<int> dp(e + 2, -1);
dp[e + 1] = 0;
dp[e] = 1;
for (int i = e - 1; i >= 0; i--)
if (jmp[i] >= 0 && dp[jmp[i]] >= 0)
dp[i] = 1 + dp[jmp[i]];
if (dp[segs[a].ss] < 0)
cout << "impossible\n";
else
cout << dp[segs[a].ss] << '\n';
}
}
signed main()
{
ios::sync_with_stdio(0);
cout.tie(0);
cin.tie(0);
srand(time(0));
int t = 1;
// cin >> t;
while (t--)
solve();
}
