#define _CRT_SECURE_NO_WARNINGS
#include <bits/stdc++.h>
//#include "temp.cpp"
#include <cstdio>
using namespace std;
#ifndef ONLINE_JUDGE
#define dbg(x) cerr << #x <<" "; print(x); cerr << endl;
#else
#define dbg(x)
#endif
#define sz(x) (int((x).size()))
#define len(x) (int)x.length()
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define clr(x) (x).clear()
#define uniq(x) x.resize(unique(all(x)) - x.begin());
#define pb push_back
#define popf pop_front
#define popb pop_back
#define ld long double
#define ll long long
void print(long long t) {cerr << t;}
void print(int t) {cerr << t;}
void print(string t) {cerr << t;}
void print(char t) {cerr << t;}
void print(double t) {cerr << t;}
void print(unsigned long long t) {cerr << t;}
void print(long double t) {cerr << t;}
template <class T, class V> void print(pair <T, V> p);
template <class T> void print(vector <T> v);
template <class T> void print(set <T> v);
template <class T, class V> void print(map <T, V> v);
template <class T> void print(multiset <T> v);
template <class T> void print(T v[],T n) {cerr << "["; for(int i = 0; i < n; i++) {cerr << v[i] << " ";} cerr << "]";}
template <class T, class V> void print(pair <T, V> p) {cerr << "{"; print(p.first); cerr << ","; print(p.second); cerr << "}";}
template <class T> void print(vector <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T> void print(set <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T> void print(multiset <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T, class V> void print(map <T, V> v) {cerr << "[ "; for (auto i : v) {print(i); cerr << " ";} cerr << "]";}
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
#define nl '\n'
// for grid problems
int dx[8] = {-1,0,1,0,1,-1,1,-1};
int dy[8] = {0,1,0,-1,1,1,-1,-1};
// lowest / (1 << 17) >= 1e5 / (1 << 18) >= 2e5 / (1 << 21) >= 1e6
void fastIO() {
ios_base::sync_with_stdio(false);
cin.tie(nullptr); cout.tie(nullptr);
}
// file in/out
void setIO(string str = "") {
fastIO();
if (str != "") {
freopen((str + ".in").c_str(), "r", stdin);
freopen((str + ".out").c_str(), "w", stdout);
}
}
// Indexed Set
template <class T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
const int N = 2e5 + 10;
vector<int> adj[N], dir[N];
int n, m, p[N], vis[N];
bool flag;
void dfs(int node, int parent) {
p[node] = parent;
for(auto i: adj[node]) {
if(i == parent) continue;
dfs(i, node);
}
}
void dfsCycle(int node) {
vis[node] = 1;
for(auto i: dir[node]) {
if(vis[i] == 1) {
flag = true;
return;
} else if(!vis[i]) {
dfsCycle(i);
}
if(flag) {
return;
}
}
vis[node] = 2;
}
void clear() {
flag = false;
for(int i = 1; i <= n; i++) {
adj[i].clear(), dir[i].clear();
}
memset(vis, false, sizeof(vis));
}
void solve_() {
clear();
cin >> n;
for(int i = 1; i <= n - 1; i++) {
int a, b; cin >> a >> b;
adj[a].push_back(b);
adj[b].push_back(a);
}
cin >> m;
vector<vector<int>> paths;
vector<pair<int, int>> start_end;
for(int i = 1; i <= m; i++) {
int a, b; cin >> a >> b;
start_end.push_back({a, b});
dfs(a, -1);
int node = b;
vector<int> nodes;
while(node != -1) {
nodes.push_back(node);
node = p[node];
}
sort(all(nodes));
paths.push_back(nodes);
}
// check for every pair
for(int i = 0; i < m; i++) {
int st = start_end[i].first, en = start_end[i].second;
for(int j = i + 1; j < m; j++) {
auto it = lower_bound(all(paths[j]), st);
if(it != paths[j].end() && *it == st) {
dir[j].push_back(i);
}
it = lower_bound(all(paths[j]), en);
if(it != paths[j].end() && *it == en) {
dir[i].push_back(j);
}
}
}
// check for cycles
for(int i = 0; i < m; i++) {
if(!vis[i]) {
dfsCycle(i);
if(flag) {
clear();
cout << "No" << endl;
return;
}
}
}
cout << "Yes" << endl;
clear();
}
int main () {
setIO("");
auto solve = [&](int test_case)-> void {
while(test_case--) {
solve_();
}
};
int test_cases = 1; cin >> test_cases;
solve(test_cases);
return 0;
}
Compilation message
jail.cpp: In function 'void setIO(std::string)':
jail.cpp:64:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
64 | freopen((str + ".in").c_str(), "r", stdin);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
jail.cpp:65:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
65 | freopen((str + ".out").c_str(), "w", stdout);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
5 ms |
10452 KB |
Output is correct |
2 |
Correct |
5 ms |
10416 KB |
Output is correct |
3 |
Correct |
6 ms |
10452 KB |
Output is correct |
4 |
Incorrect |
31 ms |
10520 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
7 ms |
10452 KB |
Output is correct |
2 |
Correct |
5 ms |
10412 KB |
Output is correct |
3 |
Incorrect |
6 ms |
10452 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
7 ms |
10452 KB |
Output is correct |
2 |
Correct |
5 ms |
10412 KB |
Output is correct |
3 |
Incorrect |
6 ms |
10452 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
7 ms |
10452 KB |
Output is correct |
2 |
Correct |
5 ms |
10412 KB |
Output is correct |
3 |
Incorrect |
6 ms |
10452 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
7 ms |
10452 KB |
Output is correct |
2 |
Correct |
5 ms |
10412 KB |
Output is correct |
3 |
Incorrect |
6 ms |
10452 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
6 ms |
10452 KB |
Output is correct |
2 |
Correct |
6 ms |
10452 KB |
Output is correct |
3 |
Correct |
6 ms |
10452 KB |
Output is correct |
4 |
Correct |
6 ms |
10504 KB |
Output is correct |
5 |
Incorrect |
52 ms |
10452 KB |
Output isn't correct |
6 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
5 ms |
10452 KB |
Output is correct |
2 |
Correct |
5 ms |
10416 KB |
Output is correct |
3 |
Correct |
6 ms |
10452 KB |
Output is correct |
4 |
Incorrect |
31 ms |
10520 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |