#include <bits/stdc++.h>
using namespace std;
typedef int64_t ll;
const int N = 120'005;
vector<array<int, 2>> adj[N];
//0: increasing, 1: decreasing, {ancestor, last weight}
array<int, 3> bl[2][18][N];
int st[N], en[N], curt;
void dfs(int i, int par, int part) {
bl[0][0][i] = {par, part, part};
bl[1][0][i] = {par, part, part};
for (int j = 1; j < 18; j++) {
bl[0][j][i] = bl[0][j - 1][i];
auto [lst, lstt, mx] = bl[0][j][i];
if (lstt <= bl[0][0][lst][1]) {
bl[0][j][i] = bl[0][j - 1][lst];
bl[0][j][i][2] = max(bl[0][j][i][2], mx);
}
}
for (int j = 1; j < 18; j++) {
bl[1][j][i] = bl[1][j - 1][i];
auto [lst, lstt, mx] = bl[1][j][i];
if (lstt >= bl[1][0][lst][1]) {
bl[1][j][i] = bl[1][j - 1][lst];
bl[1][j][i][2] = max(bl[1][j][i][2], mx);
}
}
st[i] = curt++;
for (auto [nxt, t] : adj[i]) {
if (nxt == par) continue;
dfs(nxt, i, t);
}
en[i] = curt;
}
bool lca(int l, int b) {
if (st[l] <= st[b] && en[b] <= en[l]) {
return 1;
}
return 0;
}
array<int, 2> check(int t, int a, int b) {
int mx = -1e9, high = bl[t][17][a][0];
if (!lca(high, b)) {
return {int(1e9), 0};
}
if (a == high) {
return {int(-1e9), (t == 1? 1 : -1) * int(1e9)};
}
for (int j = 17; j >= 0; j--) {
if (!lca(bl[t][j][a][0], b) && !lca(bl[t][j][a][0], high)) {
mx = max(mx, bl[t][j][a][2]);
a = bl[t][j][a][0];
}
}
return {max(mx, bl[t][0][a][2]), bl[t][0][a][1]};
}
int main() {
ios_base::sync_with_stdio(0), cin.tie(0);
int n, q;
cin >> n >> q;
q += n - 1;
pair<char, vector<int>> v[q];
for (int i = 0; i < q; i++) {
cin >> v[i].first;
if (v[i].first == 'S') {
int a, b;
cin >> a >> b;
adj[a].push_back({b, i});
adj[b].push_back({a, i});
} else if (v[i].first == 'Q') {
int a, b;
cin >> a >> b;
v[i].second = {a, b};
} else {
int a;
cin >> a;
}
}
dfs(1, 1, 0);
for (int i = 0; i < q; i++) {
if (v[i].first != 'Q') {
continue;
}
int a = v[i].second[0], b = v[i].second[1];
array<int, 2> l = check(1, a, b), r = check(0, b, a);
if (l[0] <= i && r[0] <= i && l[1] >= r[1]) {
cout << "yes\n";
} else {
cout << "no\n";
}
}
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
34 ms |
62544 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
34 ms |
62544 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
37 ms |
62548 KB |
Output is correct |
2 |
Correct |
213 ms |
73928 KB |
Output is correct |
3 |
Correct |
211 ms |
73980 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
37 ms |
62548 KB |
Output is correct |
2 |
Correct |
213 ms |
73928 KB |
Output is correct |
3 |
Correct |
211 ms |
73980 KB |
Output is correct |
4 |
Incorrect |
31 ms |
63056 KB |
Extra information in the output file |
5 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
29 ms |
62468 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
29 ms |
62468 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
29 ms |
62476 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
29 ms |
62476 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
29 ms |
62544 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
29 ms |
62544 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
31 ms |
62544 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
31 ms |
62544 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |