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ID	Problem	Submitter	Result	Time	Memory	Language	File size	Submit time	Judge time
#537217	#8551. DFS Order 5	obiwan114	WA	31ms	5640kb	C++20	2.7kb	2024-08-29 23:27:51	2024-08-29 23:27:52

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[2024-08-29 23:27:52]
评测

测评结果：WA
用时：31ms
内存：5640kb

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[2024-08-29 23:27:51]
提交

answer

#include <bits/stdc++.h>

using namespace std;
//#define int long long
using ll = long long;
using ull = unsigned long long;
using pii = pair<int, int>;
const int MAXX = 1e5 + 5;
vector<int>g[MAXX];
int fa[MAXX],dep[MAXX],siz[MAXX],son[MAXX],top[MAXX],dfn[MAXX],rnk[MAXX];
int lowbit(int x){return -x & x;}
void dfs1(int u){
    son[u] = -1;
    siz[u] = 1;
    for(int v : g[u]){
        if(dep[v])continue;
        dep[v] = dep[u] + 1;
        fa[v] = u;
        dfs1(v);
        siz[u] += siz[v];
        if(son[u] == -1 || siz[v] > siz[son[u]]){
            son[u] = v;
        }
    }
}
int cnt = 0;
void dfs2(int u,int t){
    cnt++;
    dfn[u] = cnt;
    rnk[cnt] = u;
    top[u] = t;
    if(son[u] == -1)return;
    dfs2(son[u],t);
    for(int v : g[u]){
        if(v == fa[u])continue;
        if(v == son[u])continue;
        dfs2(v,v);
    }
}
int n,q;
int a[MAXX];
vector<int>sum;
int lca(int u, int v) {
    while (top[u] != top[v]) {
        if (dep[top[u]] > dep[top[v]])
            u = fa[top[u]];
        else
            v = fa[top[v]];
    }
    return dep[u] > dep[v] ? v : u;
}
int query(int x){
    int res = 0;
    while(x){
        res += sum[x];
        x -= lowbit(x);
    }
    return res;
}
void update(int x){
    while(x <= n){
        sum[x]++;
        x += lowbit(x);
    }
}
void solve() {
    int k;
    cin >> k;
    for(int i = 1;i <= k;i++){
        cin >> a[i];
    }
    sum = vector<int>(n + 2);
    vector<int>vis(n + 2);
    vis[a[1]] = 1;
    update(dfn[a[1]]);
    stack<int>st;
    for(int i = 2;i <= k;i++){
        int x = a[i - 1];
        int y = a[i];
        if(x != fa[y] && son[x] != -1){
            cout << "No\n";
            return;
        }
        if(x != fa[y]){
            int l = lca(x,y);
            while(!st.empty()){
                int t = st.top();
                if(dep[t] <= dep[l])break;
                st.pop();
                if(query(dfn[t] + siz[t] - 1) - query(dfn[t] - 1) < siz[t]){
                    cout << "No\n";
                    return;
                }
            }
            x = l;
        }
        if(x != fa[y]){
            cout << "No\n";
            return;
        }
        if(query(dfn[y] + siz[y] - 1) - query(dfn[y] - 1)){
            cout << "No\n";
            return;
        }
    }
    cout << "Yes\n";
}

signed main() {
    ios::sync_with_stdio(false), cin.tie(0);
    cin >> n >> q;
    for(int i = 1;i < n;i++){
        int u,v;
        cin >> u >> v;
        g[u].push_back(v);
        g[v].push_back(u);
    }
    dep[1] = 1;
    dfs1(1);
    dfs2(1,1);
    while (q--) {
        solve();
    }
    return 0;
}

Source code, Language: C++20

Details

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Test #1:

score: 100

Accepted

time: 1ms

memory: 3904kb

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: 31ms

memory: 5640kb

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 899th words differ - expected: 'No', found: 'Yes'