QOJ.ac
QOJ
ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
---|---|---|---|---|---|---|---|---|---|
#465296 | #8551. DFS Order 5 | ucup-team191# | WA | 30ms | 9060kb | C++14 | 3.1kb | 2024-07-06 19:57:22 | 2024-07-06 19:57:23 |
Judging History
answer
#include<bits/stdc++.h>
using namespace std;
typedef long long llint;
typedef pair <int, int> pi;
typedef vector <int> vi;
const int MAXN = 100005;
const int LOG = 19;
int n, q;
int par[MAXN][LOG], dub[MAXN], bio[MAXN], broj_djece[MAXN], deg[MAXN];
vector <int> v[MAXN];
void dfs (int x, int rod) {
par[x][0] = rod;
dub[x] = 1 + dub[rod];
for (auto sus : v[x]) {
if (sus == rod) continue;
dfs(sus, x);
broj_djece[x]++;
}
}
void precompute_lca () {
for (int i = 1; i < LOG; i++) {
for (int j = 1; j <= n; j++) {
par[j][i] = par[par[j][i - 1]][i - 1];
}
}
}
int kth (int x, int k) {
int pot = 0;
while (k > 0) {
if (k % 2 == 1) x = par[x][pot];
k /= 2;
pot++;
}
return x;
}
int lca (int a, int b) {
if (dub[a] < dub[b]) swap(a, b);
a = kth(a, dub[a] - dub[b]);
if (a == b) return a;
for (int i = LOG - 1; i >= 0; i--) {
if (par[i][a] != par[i][b]) {
a = par[i][a];
b = par[i][b];
}
}
return par[a][0];
}
bool ima_duplica (const vi& r) {
for (auto x : r) {
bio[x] = 0;
}
for (auto x : r) {
bio[x]++;
if (bio[x] == 2) return 1;
}
return 0;
}
bool popaj (vector <pi> &st) {
int node = st.back().first, tip = st.back().second;
if (tip == 1) {
st.pop_back();
return 1;
}
if (deg[node] == broj_djece[node]) {
st.pop_back();
deg[par[node][0]]++;
return 1;
}
return 0;
}
bool solve (const vi& r) {
if (ima_duplica(r)) return 0;
vector <pi> st;
st.push_back({r[0], 0});
for (auto x : r) {
deg[x] = 0;
}
for (int i = 1; i < (int)r.size(); i++) {
int novi = r[i];
int stari = st.back().first;
int L = lca(stari, novi);
if (L == novi) {
return 0;
}
if (L == stari) {
if (par[novi][0] != stari) {
return 0;
}
st.push_back({novi, 0});
} else {
while (!st.empty() && lca(st.back().first, novi) != st.back().first) {
if (popaj(st) == 0) return 0;
}
if (st.empty() || st.back().first != L) {
st.push_back({L, 1});
}
if (par[novi][0] != L) {
return 0;
}
st.push_back({novi, 0});
}
}
return 1;
}
int main () {
ios_base::sync_with_stdio(false);
cin.tie(0);
cin >> n >> q;
for (int i = 0; i < n - 1; i++) {
int a, b;
cin >> a >> b;
v[a].push_back(b);
v[b].push_back(a);
}
dfs(1, 0);
precompute_lca();
for (int i = 0; i < q; i++) {
int siz;
cin >> siz;
vi r(siz);
for (int j = 0; j < siz; j++) {
cin >> r[j];
}
int res = solve(r);
if (res) cout << "Yes\n"; else cout << "No\n";
}
return 0;
}
Details
Tip: Click on the bar to expand more detailed information
Test #1:
score: 100
Accepted
time: 0ms
memory: 9060kb
input:
6 7 1 2 1 3 2 4 3 5 2 6 2 4 1 2 4 2 2 4 3 2 4 4 2 4 5 2 4 6 6 1 2 6 4 3 5
output:
No No Yes No No Yes Yes
result:
ok 7 tokens
Test #2:
score: -100
Wrong Answer
time: 30ms
memory: 9012kb
input:
10 100000 7 2 1 7 7 10 8 6 8 7 1 3 4 5 9 5 5 8 8 8 9 7 2 8 1 6 1 4 8 3 5 2 6 7 10 3 9 9 1 1 1 8 10 3 2 9 3 8 7 3 7 5 6 2 8 5 9 1 6 3 4 6 2 1 3 5 8 9 2 4 9 1 3 2 1 5 5 8 5 1 7 9 10 5 2 9 2 6 4 10 6 3 8 3 4 5 8 2 8 4 9 4 10 1 2 4 3 3 6 3 1 3 6 1 1 6 8 3 1 3 7 3 2 3 9 1 5 4 3 7 8 10 9 4 2 3 10 2 5 4 3 ...
output:
No No No Yes No No No No Yes No No No No No No Yes No No No No No No No No No No No No No No No Yes No No No No No No Yes No No No No No Yes Yes No No No No No No No No No No No No No No No No No No No No No No No No Yes No No Yes Yes No No No No Yes No No No No No No No No No No No No No No No No N...
result:
wrong answer 146th words differ - expected: 'Yes', found: 'No'