#include<bits/stdc++.h>
#define taskname "C"
typedef long long ll;
using namespace std;
template<class T>bool minimize(T& a, T b){
if(a > b){
a = b;
return true;
}
return false;
}
template<class T>void maximize(T& a, T b){
if(a < b){
a = b;
}
}
const int INF = 1e9;
int n, q;
namespace sub2{
void solve(){
vector<int>L(n + 1), R(n + 1);
for(int i = 1; i <= n; i++){
cin >> L[i] >> R[i];
}
vector<vector<int>>dp(n + 1, vector<int>(n + 1, INF));
dp[1][n] = 0;
for(int len = n - 2; len > -1; len--){
for(int l = 1; true; l++){
int r = l + len;
if(r > n){
break;
}
for(int i = l; i <= r; i++){
minimize(dp[l][r], dp[min(L[i], l)][max(R[i], r)] + 1);
}
}
}
cin >> q;
for(int _ = 0; _ < q; _++){
int x;
cin >> x;
cout << (dp[x][x] == INF ? -1 : dp[x][x]) << "\n";
}
}
}
namespace sub3{
struct Data{
int x, y;
bool w;
Data(){}
Data(int x, int y, bool w){
this->x = x;
this->y = y;
this->w = w;
}
};
void solve(){
vector<int>L(n + 1), R(n + 1);
for(int i = 1; i <= n; i++){
cin >> L[i] >> R[i];
}
vector<vector<vector<Data>>>g(n + 1, vector<vector<Data>>(n + 1));
for(int l = 1; l <= n; l++){
int bl = L[l], br = R[l];
g[bl][br].push_back(Data(l, l, true));
for(int r = l + 1; r <= n; r++){
minimize(bl, L[r]);
maximize(br, R[r]);
g[bl][r].push_back(Data(l, r, true));
g[l][br].push_back(Data(l, r, true));
g[l + 1][r].push_back(Data(l, r, false));
g[l][r - 1].push_back(Data(l, r, false));
}
}
vector<vector<int>>f(n + 1, vector<int>(n + 1, INF));
deque<pair<int, int>>d;
d.push_back(make_pair(1, n));
f[1][n] = 0;
while(!d.empty()){
int x, y;
tie(x, y) = d.front();
d.pop_front();
for(Data& v : g[x][y]){
if(minimize(f[v.x][v.y], f[x][y] + int(v.w))){
if(v.w){
d.push_back(make_pair(v.x, v.y));
}
else{
d.push_front(make_pair(v.x, v.y));
}
}
}
}
cin >> q;
for(int _ = 0; _ < q; _++){
int x;
cin >> x;
cout << (f[x][x] == INF ? -1 : f[x][x]) << "\n";
}
}
}
namespace sub145{
const int lim = 1e5 + 5;
vector<pair<int, bool>>g[lim];
void build(int id, int l, int r){
if(l == r){
g[l].push_back(make_pair(id + n, false));
return;
}
int m = (l + r) >> 1;
g[(id << 1) + n].push_back(make_pair(id + n, false));
g[(id << 1 | 1) + n].push_back(make_pair(id + n, false));
build(id << 1, l, m);
build(id << 1 | 1, m + 1, r);
}
void connect(int id, int l, int r, int u, int v, int x){
if(l > v || r < u){
return;
}
if(u <= l && v >= r){
g[id + n].push_back(make_pair(x, true));
return;
}
int m = (l + r) >> 1;
connect(id << 1, l, m, u, v, x);
connect(id << 1 | 1, m + 1, r, u, v, x);
}
int dis[3][lim * 5];
void bfs_01(int id, int s){
deque<int>d;
d.push_back(s);
dis[id][s] = 0;
while(!d.empty()){
int u = d.front();
d.pop_front();
for(pair<int, bool>& v : g[u]){
if(minimize(dis[id][v.first], dis[id][u] + int(v.second))){
if(v.second){
d.push_back(v.first);
}
else{
d.push_front(v.first);
}
}
}
}
}
void solve(){
build(1, 1, n);
for(int i = 1; i <= n; i++){
int l, r;
cin >> l >> r;
connect(1, 1, n, l, r, i);
}
memset(dis, 0x3f, sizeof(dis));
bfs_01(0, 1);
bfs_01(1, n);
priority_queue<pair<int, int>, vector<pair<int, int>>, greater<pair<int, int>>>pq;
for(int i = 1; i <= n; i++){
pq.push(make_pair(dis[2][i] = dis[0][i] + dis[1][i] - int(1 < i && n > i), i));
}
while(!pq.empty()){
pair<int, int>u = pq.top();
pq.pop();
if(dis[2][u.second] == u.first){
for(pair<int, bool>& v : g[u.second]){
if(minimize(dis[2][v.first], u.first + int(v.second))){
pq.push(make_pair(dis[2][v.first], v.first));
}
}
}
}
cin >> q;
for(int _ = 0; _ < q; _++){
int x;
cin >> x;
cout << (dis[2][x] < INF ? dis[2][x] : -1) << "\n";
}
}
}
int main(){
ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
if(fopen(taskname".inp", "r")){
freopen(taskname".inp", "r", stdin);
}
cin >> n;
if(n <= 300){
sub2::solve();
}
else if(n <= 2500){
sub3::solve();
}
else{
sub145::solve();
}
}
Compilation message (stderr)
passport.cpp: In function 'int main()':
passport.cpp:184:24: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
184 | freopen(taskname".inp", "r", stdin);
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