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ID题目提交者结果用时内存语言文件大小提交时间测评时间
#455459#8720. BFS 序 0Andyqian7WA 379ms75704kbC++142.8kb2024-06-26 14:30:292024-06-26 14:30:30

Judging History

你现在查看的是最新测评结果

  • [2024-06-26 14:30:30]
  • 评测
  • 测评结果:WA
  • 用时:379ms
  • 内存:75704kb
  • [2024-06-26 14:30:29]
  • 提交

answer

#include <bits/stdc++.h>
#define lowbit(x) x & -x
using namespace std;
const int MAX = 5e5 + 10;
int n, T, m, dep[MAX], q[MAX], f[MAX][20], deg[MAX], vis[MAX];
vector<int> sons[MAX];
set<int> nxt[MAX];
int anc(int s, int dis)
{
    int ans = s;
    for (int i = 0; i < 20; i++)
    {
        if (dis >> i & 1)
            ans = f[s][i];
    }
    return ans;
}
int lca(int x, int y)
{
    if (dep[x] < dep[y])
        swap(x, y);
    x = anc(x, dep[x] - dep[y]);
    for (int i = 19; ~i; i--)
    {
        if (f[x][i] != f[y][i])
        {
            x = f[x][i], y = f[y][i];
        }
    }
    return f[x][0];
}
int main()
{
    cin >> n;
    for (int i = 2; i <= n; i++)
    {
        int fa;
        cin >> fa;
        sons[fa].push_back(i), dep[i] = dep[fa] + 1, f[i][0] = fa;
    }
    for (int i = 0; i < 19; i++)
    {
        for (int j = 1; j <= n; j++)
        {
            f[j][i + 1] = f[f[j][i]][i];
        }
    }
    cin >> T;
    while (T--)
    {
        cin >> m;
        vector<int> c;
        for (int i = 1; i <= m; i++)
        {
            cin >> q[i];
            c.push_back(q[i]);
        }
        sort(c.begin(), c.end());
        int sz = c.size();
        if (unique(c.begin(), c.end()) - c.begin() != sz)
        {
            cout << "No" << endl;
            continue;
        }
        set<int> todo;
        bool sign = true;
        for (int i = 1; i < m; i++)
        {
            if (dep[q[i]] > dep[q[i + 1]])
            {
                cout << "No" << endl;
                sign = false;
                break;
            }
        }
        if (!sign)
            continue;
        for (int i = 1; i < m; i++)
        {
            if (dep[q[i]] < dep[q[i + 1]])
                continue;
            int z = lca(q[i], q[i + 1]);
            int a = anc(q[i], dep[q[i]] - dep[z] - 1);
            int b = anc(q[i + 1], dep[q[i + 1]] - dep[z] - 1);
            nxt[a].insert(b);
            deg[b]++;
            todo.insert(a), todo.insert(b);
        }
        queue<int> Q;
        for (int s : todo)
        {
            if (!deg[s])
                Q.push(s);
        }
        while (Q.size())
        {
            int t = Q.front();
            vis[t] = 1;
            Q.pop();
            for (int son : nxt[t])
            {
                deg[son]--;
                if (!deg[son])
                    Q.push(son);
            }
        }
        for (int s : todo)
        {
            nxt[s].clear();
            deg[s] = 0;
            if (!vis[s])
            {
                cout << "No" << endl;
                sign = false;
            }
            vis[s] = 0;
        }
        if (sign)
            cout << "Yes" << endl;
    }
}

详细

Test #1:

score: 100
Accepted
time: 7ms
memory: 45156kb

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: 379ms
memory: 75704kb

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
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No...

result:

wrong answer expected YES, found NO [3rd token]