#include <bits/stdc++.h> // pA
#define IO ios::sync_with_stdio(false);cin.tie(0);
#define debug(x) cerr << #x << " = " << (x) << ' '
#define endl cerr << '\n'
#define all(v) (v).begin(), (v).end()
#define SZ(v) (ll)(v).size()
#define lowbit(x) (x)&-(x)
#define pb emplace_back
#define F first
#define S second
using namespace std;
using ll = long long;
using pll = pair<ll, ll>;
const int N = 2e5+5;
//const int INF = 2e9;
int s[N], t[N], state[N], tin[N], sz[N], timer, tout[N];
vector<int> g[N];
inline void dfs(int x, int pre)
{
tin[x] = ++timer, sz[x] = 1;
for (int v : g[x])
{
if (v == pre) continue;
state[v] |= state[x];
dfs(v, x);
sz[x] += sz[v];
}
tout[x] = ++timer;
}
inline bool is_anc(int x, int y)
{
return tin[x] <= tin[y] && tout[y] <= tout[x];
}
int main(void)
{ IO
ll T, n, i, m, x, y;
cin >> T;
do {
cin >> n;
for (i=1; i <= n; ++i) tin[i] = tout[i] = sz[i] = state[i] = 0, g[i].clear();
for (i=0; i < n-1; ++i) cin >> x >> y, g[x].pb(y), g[y].pb(x);
cin >> m;
if (m > 2) assert(0);
for (i=1; i <= m; ++i) cin >> s[i] >> t[i];
state[s[2]] |= 1, state[t[2]] |= 2;
timer = 0;
dfs(s[1], 0);
if ((state[t[1]]&3) == 3)
{
cout << "No\n";
} else if (state[t[1]]&2) {
if (is_anc(t[1], s[2])) cout << "No\n";
else cout << "Yes\n";
} else if (state[t[1]]&1) {
if (!is_anc(t[1], t[2])) cout << "No\n";
else cout << "Yes\n";
} else { // debug..
if (is_anc(t[1], t[2])) cout << "No\n";
else cout << "Yes\n";
}
} while (--T);
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
8792 KB |
Output is correct |
2 |
Runtime error |
8 ms |
17500 KB |
Execution killed with signal 6 |
3 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
8792 KB |
Output is correct |
2 |
Correct |
1 ms |
8796 KB |
Output is correct |
3 |
Incorrect |
3 ms |
8792 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
8792 KB |
Output is correct |
2 |
Correct |
1 ms |
8796 KB |
Output is correct |
3 |
Incorrect |
3 ms |
8792 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
8792 KB |
Output is correct |
2 |
Correct |
1 ms |
8796 KB |
Output is correct |
3 |
Incorrect |
3 ms |
8792 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
8792 KB |
Output is correct |
2 |
Correct |
1 ms |
8796 KB |
Output is correct |
3 |
Incorrect |
3 ms |
8792 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
8796 KB |
Output is correct |
2 |
Runtime error |
8 ms |
17500 KB |
Execution killed with signal 6 |
3 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
8792 KB |
Output is correct |
2 |
Runtime error |
8 ms |
17500 KB |
Execution killed with signal 6 |
3 |
Halted |
0 ms |
0 KB |
- |