This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
using namespace std;
#define f first
#define s second
typedef long long ll;
void solve() {
    ll n; cin>>n;
    ll Q; cin>>Q;
    map<ll, ll> ord;
    vector<pair<ll, pair<ll, ll>>> v;
    for(ll i=1; i<=n; i++) {
        ll l,r; cin>>l>>r;
        v.push_back({r, {l, i}});
    }
    sort(v.begin(), v.end());
    ll p=1;
    ll lst=-1;
    for(auto [r, to]: v) {
        ll l=to.f, i=to.s;
        if(lst == -1 || (l <= lst && lst <= r)) {
            ord[p++]=i;
            lst=r;
        }
    }
    for(ll i=1; i<=Q; i++) {
        ll l, r; cin>>l>>r;
        if(ord[r]-ord[l] < 0) cout<<"impossible\n";
        else cout<<ord[r]-ord[l]<<"\n";
    }
}
signed main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
    int t=1;
    // cin>>t;
    while(t--) {
        solve();
        cout<<'\n';
    }
}
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