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QOJ

ID	Problem	Submitter	Result	Time	Memory	Language	File size	Submit time	Judge time
#455459	#8720. BFS 序 0	Andyqian7	WA	379ms	75704kb	C++14	2.8kb	2024-06-26 14:30:29	2024-06-26 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

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[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;
    }
}

Source code, Language: C++14

Details

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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]