#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;
template<typename T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
typedef long long int ll;
typedef long double ld;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL)
#define pb push_back
#define endl '\n'
#define sz(a) (int)a.size()
#define setbits(x) __builtin_popcountll(x)
#define ff first
#define ss second
#define conts continue
#define ceil2(x,y) ((x+y-1)/(y))
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define yes cout << "Yes" << endl
#define no cout << "impossible" << endl
#define rep(i,n) for(int i = 0; i < n; ++i)
#define rep1(i,n) for(int i = 1; i <= n; ++i)
#define rev(i,s,e) for(int i = s; i >= e; --i)
#define trav(i,a) for(auto &i : a)
template<typename T>
void amin(T &a, T b) {
a = min(a,b);
}
template<typename T>
void amax(T &a, T b) {
a = max(a,b);
}
#ifdef LOCAL
#include "debug.h"
#else
#define debug(x) 42
#endif
/*
read the edi a long time ago, dont remember much from there except binary lifting
*/
const int MOD = 1e9 + 7;
const int N = 1e5 + 5;
const int inf1 = int(1e9) + 5;
const ll inf2 = ll(1e18) + 5;
const int LOG = 17;
template<typename T>
struct segtree {
// https://codeforces.com/blog/entry/18051
/*=======================================================*/
struct data {
pii a;
};
data neutral = {{inf1,inf1}};
data merge(data &left, data &right) {
data curr;
curr.a = min(left.a,right.a);
return curr;
}
void create(int i, T v) {
}
void modify(int i, T v) {
tr[i].a = v;
}
/*=======================================================*/
int n;
vector<data> tr;
segtree() {
}
segtree(int siz) {
init(siz);
}
void init(int siz) {
n = siz;
tr.assign(2 * n, neutral);
}
void build(vector<T> &a, int siz) {
rep(i, siz) create(i + n, a[i]);
rev(i, n - 1, 1) tr[i] = merge(tr[i << 1], tr[i << 1 | 1]);
}
void pupd(int i, T v) {
modify(i + n, v);
for (i = (i + n) >> 1; i; i >>= 1) tr[i] = merge(tr[i << 1], tr[i << 1 | 1]);
}
data query(int l, int r) {
data resl = neutral, resr = neutral;
for (l += n, r += n; l <= r; l >>= 1, r >>= 1) {
if (l & 1) resl = merge(resl, tr[l++]);
if (!(r & 1)) resr = merge(tr[r--], resr);
}
return merge(resl, resr);
}
};
void solve(int test_case)
{
int n,q; cin >> n >> q;
vector<pii> a(n+5);
rep1(i,n) cin >> a[i].ff >> a[i].ss;
auto cmp = [&](array<int,3> ar1, array<int,3> ar2){
if(ar1[1] != ar2[1]) return ar1[1] < ar2[1];
return ar1[0] < ar2[0];
};
vector<array<int,3>> b(n+5);
rep1(i,n) b[i] = {a[i].ff,a[i].ss,i};
sort(b.begin()+1,b.begin()+n+1,cmp);
rep1(i,n) a[i] = {b[i][0],b[i][1]};
vector<int> sorted_ind(n+5);
rep1(i,n) sorted_ind[b[i][2]] = i;
int up[n+5][LOG], down[n+5][LOG];
vector<pii> enter(n+5);
rep1(i,n){
auto [l,r] = a[i];
int lo = 1, hi = n;
int first = -1;
while(lo <= hi){
int mid = (lo+hi) >> 1;
if(l <= a[mid].ss){
first = mid;
hi = mid-1;
}
else{
lo = mid+1;
}
}
assert(first != -1);
pii px = {r,i};
amax(enter[first],px);
}
pii best = {-1,-1};
int ptr = 1;
rep1(i,n){
amax(best,enter[i]);
up[i][0] = best.ss;
}
segtree<pii> st(n+5);
rep1(i,n) st.pupd(i,{a[i].ff,i});
rep1(i,n){
auto [l,r] = a[i];
int first = -1, last = -1;
int lo = 1, hi = n;
while(lo <= hi){
int mid = (lo+hi) >> 1;
if(a[mid].ss >= l){
first = mid;
hi = mid-1;
}
else{
lo = mid+1;
}
}
lo = 1, hi = n;
while(lo <= hi){
int mid = (lo+hi) >> 1;
if(a[mid].ss <= r){
last = mid;
lo = mid+1;
}
else{
hi = mid-1;
}
}
assert(first != -1 and last != -1);
pii best = st.query(first,last).a;
down[i][0] = best.ss;
}
/*
rep1(i,n){
auto [l,r] = a[i];
pii best = {r,i};
rep1(j,n){
if(j == i) conts;
auto [lx,rx] = a[j];
if(lx <= r and rx >= r){
pii px = {rx,j};
amax(best,px);
}
}
up[i][0] = best.ss;
}
rep1(i,n){
auto [l,r] = a[i];
pii best = {l,i};
rep1(j,n){
if(j == i) conts;
auto [lx,rx] = a[j];
if(l <= rx and r >= rx){
pii px = {lx,j};
amin(best,px);
}
}
down[i][0] = best.ss;
}
*/
rep1(j,LOG-1){
rep1(i,n){
up[i][j] = up[up[i][j-1]][j-1];
down[i][j] = down[down[i][j-1]][j-1];
}
}
while(q--){
int i,j; cin >> i >> j;
i = sorted_ind[i];
j = sorted_ind[j];
if(i == j){
cout << 0 << endl;
conts;
}
if(a[i].ss > a[j].ss){
no;
conts;
}
int ans = 0;
rev(b,LOG-1,0){
int p = up[i][b];
if(a[p].ss < a[j].ss){
ans += (1<<b);
i = p;
}
}
rev(b,LOG-1,0){
int p = down[j][b];
if(a[p].ff > a[i].ff){
ans += (1<<b);
j = p;
}
}
int add = inf1;
if(a[j].ff <= a[i].ss){
add = 1;
}
else{
j = down[j][0];
if(a[i].ss >= a[j].ff and a[i].ss <= a[j].ss){
add = 2;
}
}
ans += add;
if(ans > inf1) no;
else cout << ans << endl;
}
}
int main()
{
fastio;
int t = 1;
// cin >> t;
rep1(i, t) {
solve(i);
}
return 0;
}
