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ID	Problem	Submitter	Result	Time	Memory	Language	File size	Submit time	Judge time
#672206	#8551. DFS Order 5	Ri_Nai^#	WA	39ms	3640kb	C++23	3.4kb	2024-10-24 16:01:20	2024-10-24 16:01:21

Judging History

你现在查看的是最新测评结果

[2024-10-24 16:01:21]
评测

测评结果：WA
用时：39ms
内存：3640kb

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[2024-10-24 16:01:20]
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, flag = 1;
        auto dfs = [&](auto &&self, int u) -> void
        {
            ++pos;
            if (!flag)
                return;
            if (pos == m + 1)
                return;
            int v = series[pos];
            int cnt = 0;
            while (flag && pos != m + 1 && fa[series[pos]] == u)
                ++cnt, self(self, series[pos]);
            // cout << u << ' ' << cnt << endl;
            if (pos != m + 1 && cnt != edge[u].size() - (u != 1))
                flag = 0;
        };
        for (int u : need)
        {
            int last = pos;
            dfs(dfs, series[u]);
            if (pos == m + 1)
                return true;
            if (!flag)
                return false;
            if (pos - last != sz[series[u]])
                return false;
        }
        return pos == m + 1;
    };
    while (q--)
        if (solve())
            puts("Yes");
        else puts("No");
}

Source code, Language: C++23

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 100

Accepted

time: 0ms

memory: 3596kb

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: 39ms

memory: 3640kb

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 114th words differ - expected: 'No', found: 'Yes'