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ID	Problem	Submitter	Result	Time	Memory	Language	File size	Submit time	Judge time
#672129	#8551. DFS Order 5	Ri_Nai^#	WA	35ms	3680kb	C++23	3.2kb	2024-10-24 15:44:38	2024-10-24 15:44:40

Judging History

你现在查看的是最新测评结果

[2024-10-24 15:44:40]
评测

测评结果：WA
用时：35ms
内存：3680kb

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[2024-10-24 15:44:38]
提交

answer

#include <bits/stdc++.h>
using namespace std;
int main()
{
    int n, q;
    cin >> n >> q;
    vector<vector<int>> edge(n + 1);
    vector<int> son(n + 1), top(n + 1), id(n + 1),
        dep(n + 1), fa(n + 1), sz(n + 1);
    for (int i = 1; i < n; ++i)
    {
        int x, y;
        scanf("%d%d", &x, &y);
        edge[x].push_back(y);
        edge[y].push_back(x);
    }
    int num = 0;
    auto dfs = [&](auto &&self, int u, int f) -> void
    {
        fa[u] = f;
        sz[u] = 1;
        dep[u] = dep[f] + 1;
        for (int v : edge[u])
        {
            if (v == f)
                continue;
            self(self, v, u);
            sz[u] += sz[v];
            if (sz[son[u]] < sz[v])
                son[u] = v;
        }
    };
    auto dfs_ = [&](auto &&self, int u, int tp) -> void
    {
        top[u] = tp;
        id[u] = ++num;
        if (son[u])
            self(self, son[u], tp);
        for (int v : edge[u])
            if (v != fa[u] && v != son[u])
                self(self, v, v);
    };
    dfs(dfs, 1, 0);
    dfs_(dfs_, 1, 1);
    auto 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] ? u : v;
    };
    auto solve = [&]()
    {
        auto isAscent = [&](int u, int v)
        {
            return LCA(u, v) == v;
        };
        auto isValid = [&](int u, int v)
        {
            return isAscent(u, fa[v]) && !isAscent(u, v) && fa[v] != u;
        };
        auto inValid = [&](int u, int v)
        {
            return isAscent(u, v);
        };
        int m;
        scanf("%d", &m);
        vector<int> series(m + 1);
        for (int i = 1; i <= m; ++i)
            scanf("%d", &series[i]);
        vector<int> need;
        need.push_back(1);
        for (int i = 2; i <= m; ++i)
            if(isValid(series[1], series[i]))
                need.push_back(i);
            else if (inValid(series[1], series[i]))
                return false;
        for (int i = 1; i < need.size(); ++i)
            if (need[i] - need[i - 1] != sz[series[need[i - 1]]])
                return false;
        for (int i = 1; i < need.size(); ++i)
            if (dep[series[need[i]]] > dep[series[need[i - 1]]])
                return false;

        int pos = 1;
        auto dfs = [&](auto &&self, int u) -> void
        {
            ++pos;
            if (pos == m + 1)
                return;
            int v = series[pos];
            while (pos != m + 1 && fa[series[pos]] == u)
                self(self, series[pos]);
        };
        for (int u : need)
        {
            int last = pos;
            dfs(dfs, series[u]);
            // cout << last << "->" << pos << endl;
            if (pos == m + 1)
                return true;
            // cout << "this\n";
            if (pos - last != sz[series[u]])
                return false;
            // cout << "that\n";
        }
        return pos == m + 1;
    };
    while (q--)
        if (solve())
            puts("Yes");
        else puts("No");
}

Source code, Language: C++23

Details

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Test #1:

score: 100

Accepted

time: 0ms

memory: 3680kb

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: 35ms

memory: 3648kb

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
Yes
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
...

result:

wrong answer 20th words differ - expected: 'No', found: 'Yes'