#include <bits/stdc++.h>
using namespace std;
const int MAX_N = 2e5;
const int INF = 1e9;
int l[MAX_N + 1], r[MAX_N + 1], minL[MAX_N + 1], maxR[MAX_N + 1], minSufL[MAX_N + 1], maxPrefR[MAX_N + 1], dist1[MAX_N + 1], distN[MAX_N + 1], dist1R[MAX_N + 1], distNR[MAX_N + 1];
int n;
struct AINT {
struct px {
int p, x;
bool operator < ( const px &a ) const {
return x < a.x;
}
};
set<px> aint[4 * MAX_N];
void insert( int v, int l, int r, int p, int x, int y ) {
if ( l > x || r < x )
return;
aint[v].insert( { p, y } );
if ( l == r )
return;
int mid = (l + r) / 2;
insert( v * 2 + 1, l, mid, p, x, y );
insert( v * 2 + 2, mid + 1, r, p, x, y );
}
void erase( int v, int l, int r, int p, int x, int y ) {
if ( l > x || r < x )
return;
aint[v].erase( { p, y } );
if ( l == r )
return;
int mid = (l + r) / 2;
insert( v * 2 + 1, l, mid, p, x, y );
insert( v * 2 + 2, mid + 1, r, p, x, y );
}
px query( int v, int l, int r, int lq, int rq ) {
if ( l > rq || r < lq || aint[v].empty() )
return { 0, 0 };
if ( lq <= l && r <= rq )
return *aint[v].rbegin();
int mid = (l + r) / 2;
return max( query( v * 2 + 1, l, r, lq, rq ), query( v * 2 + 2, l, r, lq, rq ) );
}
} aint1, aintN;
void calc_dist1() {
struct dr {
int i, dist, maxR;
bool operator < ( const dr &x ) const {
if ( dist == x.dist )
return maxR < x.maxR;
return dist > x.dist;
}
};
for ( int i = 0; i <= n; i++ )
dist1[i] = INF, maxR[i] = 0;
priority_queue<dr> pq;
dist1[1] = 0;
maxR[1] = 0;
pq.push( { 1, dist1[1], maxR[1] } );
while ( !pq.empty() ) {
auto crt = pq.top();
pq.pop();
int i = crt.i;
auto a = aint1.query( 0, 1, n, 1, i );
while ( a.x >= i ) {
int j = a.p;
if ( dist1[i] + 1 <= dist1[j] && max( maxR[i], r[j] ) > maxR[j] ) {
dist1[j] = dist1[i] + 1;
maxR[j] = max( maxR[i], r[j] );
pq.push( { j, dist1[j], maxR[j] } );
}
aint1.erase( 0, 1, n, j, l[j], r[j] );
a = aint1.query( 0, 1, n, 1, i );
}
}
dist1[1] = 1;
maxR[1] = r[1];
}
void calc_distN() {
struct dr {
int i, dist, minL;
bool operator < ( const dr &x ) const {
if ( dist == x.dist )
return minL > x.minL;
return dist > x.dist;
}
};
for ( int i = 0; i <= n; i++ )
distN[i] = INF, minL[i] = n + 1;
priority_queue<dr> pq;
distN[n] = 0;
minL[n] = n + 1;
pq.push( { n, distN[n], minL[n] } );
while ( !pq.empty() ) {
auto crt = pq.top();
pq.pop();
int i = crt.i;
auto a = aintN.query( 0, 1, n, 1, i );
while ( a.x >= i ) {
int j = a.p;
if ( distN[i] + 1 <= distN[j] && min( minL[i], l[j] ) < minL[j] ) {
distN[j] = distN[i] + 1;
minL[j] = min( minL[i], l[j] );
pq.push( { j, distN[j], minL[j] } );
}
aintN.erase( 0, 1, n, j, l[j], r[j] );
a = aintN.query( 0, 1, n, 1, i );
}
}
distN[n] = 1;
minL[n] = r[n];
}
void calc_dist1_rest() {
for ( int i = 0; i <= n; i++ )
dist1R[i] = INF;
minSufL[n] = l[n];
for ( int i = n - 1; i >= 1; i-- )
minSufL[i] = min( minSufL[i + 1], l[i] );
dist1R[1] = 0;
for ( int i = 2; i <= n; i++ )
dist1R[i] = dist1R[minSufL[i]] + 1;
}
void calc_distN_rest() {
for ( int i = n - 1; i >= 0; i-- )
distNR[i] = INF;
for ( int i = 1; i <= n; i++ )
maxPrefR[i] = max( maxPrefR[i - 1], r[i] );
distNR[n] = 0;
for ( int i = n - 1; i >= 1; i-- )
distNR[i] = distNR[maxPrefR[i]] + 1;
}
int main() {
ios_base::sync_with_stdio( false );
cin.tie( NULL );
cout.tie( NULL );
int q;
cin >> n;
for ( int i = 1; i <= n; i++ ) {
cin >> l[i] >> r[i];
aint1.insert( 0, 1, n, i, l[i], r[i] );
aintN.insert( 0, 1, n, i, l[i], r[i] );
}
calc_dist1();
calc_distN();
calc_dist1_rest();
calc_distN_rest();
cin >> q;
while ( q-- ) {
int x;
cin >> x;
int ans = min( distN[x] + dist1R[minL[x]], dist1[x] + distNR[maxR[x]] );
cout << (ans > n ? -1 : ans) << "\n";
}
return 0;
}
Compilation message
passport.cpp: In member function 'AINT::px AINT::query(int, int, int, int, int)':
passport.cpp:52:13: warning: unused variable 'mid' [-Wunused-variable]
52 | int mid = (l + r) / 2;
| ^~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
20 ms |
82520 KB |
Output is correct |
| 2 |
Correct |
17 ms |
82524 KB |
Output is correct |
| 3 |
Correct |
15 ms |
82692 KB |
Output is correct |
| 4 |
Execution timed out |
2103 ms |
347236 KB |
Time limit exceeded |
| 5 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
16 ms |
82524 KB |
Output is correct |
| 2 |
Incorrect |
15 ms |
82656 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
16 ms |
82524 KB |
Output is correct |
| 2 |
Incorrect |
15 ms |
82656 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
16 ms |
82524 KB |
Output is correct |
| 2 |
Incorrect |
15 ms |
82656 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
20 ms |
82520 KB |
Output is correct |
| 2 |
Correct |
17 ms |
82524 KB |
Output is correct |
| 3 |
Correct |
15 ms |
82692 KB |
Output is correct |
| 4 |
Execution timed out |
2103 ms |
347236 KB |
Time limit exceeded |
| 5 |
Halted |
0 ms |
0 KB |
- |
