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QOJ

IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#603455#8720. BFS 序 0llleiRE 204ms77488kbC++204.3kb2024-10-01 16:40:312024-10-01 16:40:33

Judging History

你现在查看的是最新测评结果

  • [2024-10-01 16:40:33]
  • 评测
  • 测评结果:RE
  • 用时:204ms
  • 内存:77488kb
  • [2024-10-01 16:40:31]
  • 提交

answer

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

struct LCA {
    const int N;
    int n, idx;
    vector<int> id, rid, dep, fa;
    vector<vector<int>> e, st;

    LCA(int n) : N(__lg(n) + 1), n(n), idx(0), id(n, -1), rid(n), dep(n), fa(n), e(n), st(N, vector<int>(n)) {}

    void add(int u, int v) {
        e[u].push_back(v);
        e[v].push_back(u);
    }

    int getMin(int x, int y) {
        return dep[x] < dep[y] ? x : y;
    }

    void dfs(int u) {
        id[u] = idx;
        rid[idx] = u;
        idx++;

        for (int v : e[u]) {
            if (id[v] != -1) {
                continue;
            }

            dep[v] = dep[u] + 1;
            fa[v] = u;
            dfs(v);
        }
    }

    void work(int rt = 0) {
        dep[rt] = 1;
        dfs(rt);

        for (int i = 0; i < n; ++i) {
            st[0][i] = rid[i];
        }

        for (int i = 1; i < N; ++i) {
            for (int j = 0; j + (1 << i) - 1 < n; ++j) {
                st[i][j] = getMin(st[i - 1][j], st[i - 1][j + (1 << (i - 1))]);
            }
        }
    }

    int getLca(int x, int y) {
        if (x == y) {
            return x;
        }
        x = id[x], y = id[y];
        if (x > y) {
            swap(x, y);
        }
        ++x;
        int z = __lg(y - x + 1);
        return fa[getMin(st[z][x], st[z][y - (1 << z) + 1])];
    }
};


int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    int n;
    cin >> n;
    LCA lca(n);
    vector<vector<int>> e(n);
    for (int i = 1; i < n; ++i) {
        int f;
        cin >> f;
        --f;
        lca.add(f, i);
        e[f].push_back(i);
    }
    lca.work();

    vector<int> dep(n, -1);
    vector<int> dfn(n);
    int tot = 0;
    auto dfs = [&](auto &&self, int u) -> void {
        dfn[u] = tot++;
        for (int v : e[u]) {
            dep[v] = dep[u] + 1;
            self(self, v);
        }
    };

    dep[0] = 0;
    dfs(dfs, 0);

    int q;
    cin >> q;

    vector<vector<int>> ee(n);
    vector<int> d(n);

    auto solve = [&]() {
        int m;
        cin >> m;

        vector<int> a(m);
        vector<int> c(m);
        for (int i = 0; i < m; ++i) {
            cin >> a[i];
            --a[i];
            c[i] = a[i];
            if (i) {
                ee[a[i - 1]].push_back(a[i]);
                d[a[i]]++;
            }
        }

        for (int i = 1; i < m; ++i) {
            if (dep[a[i]] < dep[a[i - 1]]) {
                for (auto x : c) {
                    ee[x].clear();
                    d[x] = 0;
                }
                cout << "No\n";
                return;
            }
        }


        for (int i = 0; i < m;) {
            int j = i;
            while (j < m && dep[a[j]] == dep[a[i]]) {
                ++j;
            }

            for (int k = i; k < j - 1; ++k) {
                int l = lca.getLca(a[k], a[k + 1]);

                int t1 = *prev(upper_bound(e[l].begin(), e[l].end(), a[k], [&](int x, int y) {
                    return dfn[x] < dfn[y];
                }));
                int t2 = *prev(upper_bound(e[l].begin(), e[l].end(), a[k + 1], [&](int x, int y) {
                    return dfn[x] < dfn[y];
                }));

                assert(t1 != t2);
                ee[t1].push_back(t2);
                d[t2]++;
                c.push_back(t1);
                c.push_back(t2);
            }
            i = j;
        } 

        sort(c.begin(), c.end());
        c.erase(unique(c.begin(), c.end()), c.end());

        queue<int> q;
        for (auto x : c) {
            if (d[x] == 0) {
                q.push(x);
            }
        }
        int cnt = 0;

        while (q.size()) {
            int u = q.front();
            q.pop();
            ++cnt;
            for (int v : ee[u]) {
                --d[v];

                if (d[v] == 0) {
                    q.push(v);
                }
            }
        }

        for (auto x : c) {
            ee[x].clear();
            d[x] = 0;
        }

        if (cnt != c.size()) {
            cout << "No\n";
        } else {
            cout << "Yes\n";
        }
    };

    while (q--) {
        solve();
    }
    return 0;
}

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 100
Accepted
time: 0ms
memory: 3572kb

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: 0
Accepted
time: 204ms
memory: 76000kb

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
No
No
No
No
No
No
Yes
Yes
No
Yes
No
Yes
Yes
Yes
No
No
No
No
Yes
No
No
Yes
No
No
No
No
Yes
Yes
Yes
No
No
Yes
No
No
No
No
No
No
No
Yes
No
Yes
No
Yes
No
No
No
No
Yes
Yes
Yes
No
No
Yes
No
No
No
No
No
Yes
Yes
No
No
No
No
No
Yes
Yes
No
Yes
No
No
No
Yes
No
No
Yes
No
No
Yes
Yes
Yes
No
No
No
Y...

result:

ok 254 token(s): yes count is 89, no count is 165

Test #3:

score: 0
Accepted
time: 201ms
memory: 77488kb

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:

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

result:

ok 266 token(s): yes count is 102, no count is 164

Test #4:

score: 0
Accepted
time: 203ms
memory: 77276kb

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

result:

ok 252 token(s): yes count is 87, no count is 165

Test #5:

score: -100
Runtime Error

input:

10
1 1 3 3 1 3 1 3 9
10000
4 3 5 6 9
5 3 1 4 9 6
5 6 4 3 5 7
28 8 3 4 3 1 6 3 5 8 7 2 4 4 4 2 7 5 9 2 4 10 8 4 10 3 4 5 7
3 5 2 9
6 4 7 2 3 9 5
5 9 2 5 6 1
12 3 5 8 8 1 3 5 8 4 5 9 1
29 3 9 9 1 5 8 5 5 6 10 8 8 4 8 4 2 8 10 5 7 3 7 1 8 4 7 5 1 6
7 5 9 8 3 2 1 6
4 4 1 9 5
22 10 9 5 4 5 8 10 3 2 1 10 ...

output:


result: