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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#417352#8720. BFS 序 0light_ink_dots#WA 110ms105876kbC++143.1kb2024-05-22 17:52:422024-05-22 17:52:43

Judging History

你现在查看的是最新测评结果

  • [2024-05-22 17:52:43]
  • 评测
  • 测评结果:WA
  • 用时:110ms
  • 内存:105876kb
  • [2024-05-22 17:52:42]
  • 提交

answer

#include <bits/stdc++.h>
using namespace std;

int main() {
    static const int maxn = 500010, maxlg = 20;
    int n;
    scanf("%d", &n);
    static int fa[maxn];
    static vector<int> G[maxn];
    for (int i = 2; i <= n; i++) scanf("%d", fa + i), G[fa[i]].push_back(i);
    static int dfn[maxn], dep[maxn];
    static int lg[maxn], st[maxlg][maxn];
    static auto get = [](int u, int v) { return dep[u] < dep[v] ? u : v; };
    static vector<int> vec[maxn];
    function<void(int)> dfs = [&dfs](int u) {
        static int c;
        st[0][dfn[u] = ++c] = fa[u];
        for (int i : G[u]) dep[i] = dep[u] + 1, dfs(i), vec[u].push_back(dfn[i]);
        return;
    };
    dfs(1);
    for (int i = 2; i <= n; i++) lg[i] = lg[i >> 1] + 1;
    for (int l = 1; l <= lg[n]; l++)
        for (int i = 1; i + (1 << l) - 1 <= n; i++)
            st[l][i] = get(st[l - 1][i], st[l - 1][i + (1 << (l - 1))]);
    auto lca = [](int u, int v) {
        if (u == v)
            return u;
        u = dfn[u], v = dfn[v];
        if (u > v)
            swap(u, v);
        int Lg = lg[v - (++u) + 1];
        return get(st[Lg][u], st[Lg][v - (1 << Lg) + 1]);
    };
    int q;
    scanf("%d", &q);
    while (q--) {
        int m;
        bool ans = true;
        scanf("%d", &m);
        static int a[maxn];
        for (int i = 1; i <= m; i++) scanf("%d", a + i);
        static bool vis[maxn];
        static vector<int> all;
        static vector<pair<int, int>> G[maxn];
        for (int i = 1; i + 1 <= m; i++) {
            if (dep[a[i]] != dep[a[i + 1]]) {
                ans &= dep[a[i]] < dep[a[i + 1]];
                continue;
            }
            int l = lca(a[i], a[i + 1]);
            if (!vis[l])
                vis[l] = true, all.push_back(l);
            int u = *prev(upper_bound(vec[l].begin(), vec[l].end(), dfn[a[i]]));
            int v = *prev(upper_bound(vec[l].begin(), vec[l].end(), dfn[a[i + 1]]));
            G[l].emplace_back(u, v);
        }
        for (int u : all) {
            vector<int> cur;
            static vector<int> g[maxn];
            static bool vis[maxn];
            static int deg[maxn];
            for (auto e : G[u]) {
                if (!vis[e.first])
                    vis[e.first] = true, cur.push_back(e.first);
                if (!vis[e.second])
                    vis[e.second] = true, cur.push_back(e.second);
                g[e.first].push_back(e.second), deg[e.second]++;
            }
            int tot = 0;
            queue<int> q;
            for (int i : cur)
                if (!deg[i])
                    q.push(i);
            while (!q.empty()) {
                int u = q.front();
                q.pop(), tot++;
                for (int i : g[u])
                    if (!(--deg[i]))
                        q.push(i);
            }
            ans &= tot == cur.size();
            for (int i : cur) vis[i] = false, deg[i] = 0, g[i].clear();
            G[u].clear(), vis[u] = false;
        }
        printf(ans ? "Yes\n" : "No\n");
        all.clear();
    }
    return 0;
}

Details

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Test #1:

score: 100
Accepted
time: 4ms
memory: 58852kb

input:

6
1 1 3 2 4
10
4 3 6 2 5
1 4
3 2 4 5
5 2 5 4 6 3
3 1 4 2
3 5 6 3
5 4 5 2 6 1
4 4 3 2 5
4 4 6 2 3
3 3 2 6

output:

No
Yes
Yes
No
No
No
No
No
No
Yes

result:

ok 10 token(s): yes count is 3, no count is 7

Test #2:

score: -100
Wrong Answer
time: 110ms
memory: 105876kb

input:

300000
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1...

output:

No
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
Yes
Yes
Yes
Yes
Yes
Yes
No
Yes
Yes
Yes
Yes
No
Yes
Yes
No
Yes
Yes
Yes
Yes
Yes
Yes
No
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
Yes
Yes
No
Yes
Yes
No
No
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
Yes
Yes...

result:

wrong answer expected NO, found YES [5th token]