#include <bits/stdc++.h>
#ifndef _DEBUG
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx")
#endif
using namespace std;
#define int int64_t
template <class T>
istream &operator>>(istream &in, vector<T> &v)
{
for (T &x : v)
in >> x;
return in;
}
struct Range
{
int s, e, i;
bool operator<(Range other)
{
return tuple<int, int, int>{s, e, i} < tuple<int, int, int>{other.s, other.e, other.i};
}
};
int n, q;
vector<Range> ranges, sR;
signed main()
{
cin.tie(0);
ios_base::sync_with_stdio(false);
cin >> n >> q;
ranges = vector<Range>(n);
for (int i = 0; i < n; i++)
{
cin >> ranges[i].s >> ranges[i].e;
ranges[i].i = i;
}
sR = ranges;
sort(sR.begin(), sR.end());
while (q--)
{
int s, e;
cin >> s >> e;
s--, e--;
set<pair<int, int>> ongoing;
int t = ranges[s].e;
int index = s;
int i = 0;
int cost = 0;
while (true)
{
if (index == e)
{
cout << cost << "\n";
goto next;
}
while (i < n && sR[i].s <= t)
{
if (sR[i].e >= t)
ongoing.insert({sR[i].e, sR[i].i});
i++;
}
while (ongoing.size() && prev(ongoing.end())->first > ranges[e].e) // remove invalid ones -> where you would jump too far
ongoing.erase(prev(ongoing.end()));
if (!ongoing.size())
{
cout << "impossible\n";
goto next;
}
cost++;
t = prev(ongoing.end())->first;
index = prev(ongoing.end())->second;
ongoing = set<pair<int, int>>();
}
next:
continue;
}
}
