#include <bits/stdc++.h>
#define ll long long
#define ld long double
#define sp ' '
#define en '\n'
#define smin(a, b) a = min(a, b)
#define smax(a, b) a = max(a, b)
using namespace std;
const int N = 120000 + 2;
const int inf = 1e9;
vector<array<int, 2>> g[N];
int par[N][17], in[N], out[N], val[N], donji[N], dep[N], tsz;
bool inc[N][17], dek[N][17];
void Dfs(int s, int e) {
in[s] = ++tsz;
par[s][0] = e;
inc[s][0] = 1;
dek[s][0] = 1;
for (int i = 1; i < 17; i++) {
int u = par[s][i - 1];
par[s][i] = par[u][i - 1];
inc[s][i] = inc[s][i - 1] & inc[u][i - 1] & (donji[u] < val[u]);
dek[s][i] = dek[s][i - 1] & dek[u][i - 1] & (donji[u] > val[u]);
}
for (auto zz : g[s]) {
int u = zz[0]; int i = zz[1];
if (u == e) continue;
dep[u] = dep[s] + 1;
donji[s] = i;
val[u] = i;
Dfs(u, s);
}
out[s] = tsz;
}
bool Ancestor(int u, int v) {
return in[u] <= in[v] && out[v] <= out[u];
}
int Lca(int u, int v) {
if (Ancestor(u, v)) return u;
if (Ancestor(v, u)) return v;
for (int i = 16; i >= 0; i--) {
if (par[u][i] && !Ancestor(par[u][i], v)) u = par[u][i];
}
return par[u][0];
}
int Kth(int u, int k) {
for (int i = 16; i >= 0; i--) {
if ((1 << i) & k) u = par[u][i];
}
return u;
}
bool MozeI(int u, int v) {
if (u == v) return 1;
int r = dep[u] - dep[v];
bool ans = 1;
for (int i = 16; i >= 0 && ans; i--) {
if ((1 << i) & r) {
ans &= inc[u][i];
r -= (1 << i);
if (r != 0) ans &= (val[Kth(u, (1 << i) - 1)] < val[par[u][i]]);
u = par[u][i];
}
}
return ans;
}
bool MozeD(int u, int v) {
if (u == v) return 1;
int r = dep[u] - dep[v];
bool ans = 1;
for (int i = 16; i >= 0 && ans; i--) {
if ((1 << i) & r) {
ans &= dek[u][i];
r -= (1 << i);
if (r != 0) ans &= (val[Kth(u, (1 << i) - 1)] > val[par[u][i]]);
u = par[u][i];
}
}
return ans;
}
int main() {
ios::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
int n, k;
cin >> n >> k;
if (n <= 4000) assert(k <= 4000);
vector<array<int, 3>> all;
int cnt = 0;
for (int i = 0; i < n + k - 1; i++) {
char ch; cin >> ch;
int u, v;
if (ch == 'C') {
cin >> u;
continue;
}
cin >> u >> v;
if (ch == 'S') {
g[u].push_back({v, cnt});
g[v].push_back({u, cnt});
all.push_back({0, u, v});
cnt += 1;
}
else all.push_back({1, u, v});
}
Dfs(1, 0);
cnt = 0;
/*for (int i = 1; i <= n; i++) {
cout << i << sp << val[i] << " : ";
for (int j = 0; j <= 2; j++) {
cout << par[i][j] << sp << inc[i][j] << sp << dek[i][j] << en;
}
}*/
for (int i = 0; i < all.size(); i++) {
if (all[i][0] == 0) {
cnt += 1;
continue;
}
int u = all[i][1]; int v = all[i][2];
swap(u, v);
if (u == v) {
cout << "yes" << en;
continue;
}
int lca = Lca(u, v);
int uu, vv; uu = vv = -1;
if (u != lca) uu = val[Kth(u, dep[u] - dep[lca] - 1)];
if (v != lca) vv = val[Kth(v, dep[v] - dep[lca] - 1)];
bool ans = MozeI(u, lca) & MozeD(v, lca);
if (uu != -1 && vv != -1) ans &= uu < vv;
int lst = val[v];
if (v == lca) lst = uu;
ans &= lst < cnt;
if (ans) cout << "yes" << en;
else cout << "no" << en;
}
return 0;
}
Compilation message
servers.cpp: In function 'int main()':
servers.cpp:113:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::array<int, 3> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
113 | for (int i = 0; i < all.size(); i++) {
| ~~^~~~~~~~~~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
7 ms |
6228 KB |
Execution killed with signal 6 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
7 ms |
6228 KB |
Execution killed with signal 6 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
5 ms |
6232 KB |
Execution killed with signal 6 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
5 ms |
6232 KB |
Execution killed with signal 6 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
5 ms |
6228 KB |
Execution killed with signal 6 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
5 ms |
6228 KB |
Execution killed with signal 6 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
8 ms |
6252 KB |
Execution killed with signal 6 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
8 ms |
6252 KB |
Execution killed with signal 6 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
5 ms |
6228 KB |
Execution killed with signal 6 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
5 ms |
6228 KB |
Execution killed with signal 6 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
8 ms |
6172 KB |
Execution killed with signal 6 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
8 ms |
6172 KB |
Execution killed with signal 6 |
2 |
Halted |
0 ms |
0 KB |
- |