#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
const int MAXN = 2e5;
int Q, N, NN, M;
vector<int> adj[MAXN+10];
pii A[MAXN+10];
int idx[MAXN+10];
vector<int> adj2[MAXN*5+10];
vector<int> radj2[MAXN*5+10];
int dep[MAXN+10], par[MAXN+10], sz[MAXN+10];
void dfs(int now, int bef, int d)
{
dep[now]=d;
par[now]=bef;
sz[now]=1;
for(int nxt : adj[now])
{
if(nxt==bef) continue;
dfs(nxt, now, d+1);
sz[now]+=sz[nxt];
}
}
void addEdge(int u, int v)
{
//printf("%d %d\n", u, v);
adj2[u].push_back(v);
radj2[v].push_back(u);
}
void init(int node, int tl, int tr)
{
if(tl==tr)
{
idx[tl]=node;
return;
}
int mid=tl+tr>>1;
init(node*2, tl, mid);
init(node*2+1, mid+1, tr);
addEdge(M+node*2, M+node);
addEdge(M+node*2+1, M+node);
addEdge(M+N+N+node, M+N+N+node*2);
addEdge(M+N+N+node, M+N+N+node*2+1);
}
void get(int node, int tl, int tr, int l, int r, vector<int> &V)
{
if(r<tl || tr<l) return;
if(l<=tl && tr<=r)
{
V.push_back(node);
return;
}
int mid=tl+tr>>1;
get(node*2, tl, mid, l, r, V);
get(node*2+1, mid+1, tr, l, r, V);
}
int dfn[MAXN+10], head[MAXN+10], dcnt;
void hld(int now, int bef)
{
dfn[now]=++dcnt;
int heavy=0;
for(int nxt : adj[now]) if(nxt!=bef && sz[heavy]<sz[nxt]) heavy=nxt;
if(!heavy) return;
head[heavy]=head[now];
hld(heavy, now);
for(int nxt : adj[now]) if(nxt!=bef && nxt!=heavy)
{
head[nxt]=nxt;
hld(nxt, now);
}
}
int vis[MAXN*5+10];
vector<int> S;
void dfs2(int now)
{
vis[now]=1;
for(int nxt : adj2[now]) if(!vis[nxt]) dfs2(nxt);
S.push_back(now);
}
int scc[MAXN+10], scnt;
void dfs3(int now)
{
scc[now]=scnt;
for(int nxt : radj2[now]) if(!scc[nxt]) dfs3(nxt);
}
bool solve()
{
scanf("%d", &N);
for(int i=1; i<N; i++)
{
int u, v;
scanf("%d%d", &u, &v);
adj[u].push_back(v);
adj[v].push_back(u);
}
scanf("%d", &M);
for(int i=1; i<=M; i++)
{
scanf("%d%d", &A[i].first, &A[i].second);
}
NN=N*4+M;
init(1, 1, N);
dfs(1, 0, 1);
head[1]=1;
hld(1, 0);
for(int i=1; i<=M; i++)
{
addEdge(i, idx[dfn[A[i].first]]+M);
addEdge(idx[dfn[A[i].second]]+M+N+N, i);
}
for(int i=1; i<=M; i++)
{
int u=A[i].first, v=A[i].second;
while(head[u]!=head[v])
{
if(dep[u]>dep[v]) swap(u, v);
vector<int> V;
get(1, 1, N, dfn[head[v]], dfn[v], V);
for(auto it : V)
{
addEdge(it+M, i);
addEdge(i, it+M+N+N);
}
v=par[head[v]];
}
if(dep[u]>dep[v]) swap(u, v);
vector<int> V;
get(1, 1, N, dfn[u], dfn[v], V);
for(auto it : V)
{
addEdge(it+M, i);
addEdge(i, it+M+N+N);
}
}
for(int i=1; i<=NN; i++) if(!vis[i]) dfs2(i);
reverse(S.begin(), S.end());
for(auto it : S) if(!scc[it]) scnt++, dfs3(it);
set<int> SS;
for(int i=1; i<=M; i++) SS.insert(scc[i]);
return SS.size()==M;
}
void clear()
{
for(int i=1; i<=N; i++)
{
adj[i].clear();
}
for(int i=1; i<=NN; i++)
{
adj2[i].clear();
radj2[i].clear();
vis[i]=0;
scc[i]=0;
}
S.clear();
dcnt=0;
scnt=0;
}
int main()
{
scanf("%d", &Q);
while(Q--)
{
if(solve()) printf("Yes\n");
else printf("No\n");
clear();
}
}
Compilation message
jail.cpp: In function 'void init(int, int, int)':
jail.cpp:46:12: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
46 | int mid=tl+tr>>1;
| ~~^~~
jail.cpp: In function 'void get(int, int, int, int, int, std::vector<int>&)':
jail.cpp:64:12: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
64 | int mid=tl+tr>>1;
| ~~^~~
jail.cpp: In function 'bool solve()':
jail.cpp:166:18: warning: comparison of integer expressions of different signedness: 'std::set<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
166 | return SS.size()==M;
| ~~~~~~~~~^~~
jail.cpp:106:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
106 | scanf("%d", &N);
| ~~~~~^~~~~~~~~~
jail.cpp:110:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
110 | scanf("%d%d", &u, &v);
| ~~~~~^~~~~~~~~~~~~~~~
jail.cpp:114:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
114 | scanf("%d", &M);
| ~~~~~^~~~~~~~~~
jail.cpp:117:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
117 | scanf("%d%d", &A[i].first, &A[i].second);
| ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
jail.cpp: In function 'int main()':
jail.cpp:189:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
189 | scanf("%d", &Q);
| ~~~~~^~~~~~~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
31 ms |
51916 KB |
Output is correct |
2 |
Correct |
26 ms |
52020 KB |
Output is correct |
3 |
Correct |
29 ms |
51952 KB |
Output is correct |
4 |
Incorrect |
41 ms |
52084 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
24 ms |
51924 KB |
Output is correct |
2 |
Correct |
24 ms |
51908 KB |
Output is correct |
3 |
Incorrect |
32 ms |
52004 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
24 ms |
51924 KB |
Output is correct |
2 |
Correct |
24 ms |
51908 KB |
Output is correct |
3 |
Incorrect |
32 ms |
52004 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
24 ms |
51924 KB |
Output is correct |
2 |
Correct |
24 ms |
51908 KB |
Output is correct |
3 |
Incorrect |
32 ms |
52004 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
24 ms |
51924 KB |
Output is correct |
2 |
Correct |
24 ms |
51908 KB |
Output is correct |
3 |
Incorrect |
32 ms |
52004 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
24 ms |
51936 KB |
Output is correct |
2 |
Correct |
23 ms |
51948 KB |
Output is correct |
3 |
Correct |
27 ms |
51960 KB |
Output is correct |
4 |
Correct |
25 ms |
51952 KB |
Output is correct |
5 |
Incorrect |
58 ms |
51944 KB |
Output isn't correct |
6 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
31 ms |
51916 KB |
Output is correct |
2 |
Correct |
26 ms |
52020 KB |
Output is correct |
3 |
Correct |
29 ms |
51952 KB |
Output is correct |
4 |
Incorrect |
41 ms |
52084 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |