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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
#602638	#8720. BFS 序 0	ucup-team902^#	WA	180ms	52664kb	C++23	2.7kb	2024-10-01 11:26:42	2024-10-01 11:26:43

Judging History

你现在查看的是最新测评结果

[2024-10-01 11:26:43]
评测

测评结果：WA
用时：180ms
内存：52664kb

查看

[2024-10-01 11:26:42]
提交

answer

#include <bits/stdc++.h>
using namespace std;
int n;
vector<int> G[400005], G2[400005];
int fa[400005][20];
int dep[400005], b[400005];
int LCA(int u, int v) {
    if (dep[u] < dep[v]) swap(u, v);
    for (int i = 19; ~i; i--)
        if (dep[fa[u][i]] >= dep[v]) u = fa[u][i];
    if (u == v) return v;
    for (int i = 19; ~i; i--)
        if (fa[u][i] != fa[v][i]) {
            u = fa[u][i], v = fa[v][i];
        }
    return fa[u][0];
}

int dis(int u, int v) {
    return dep[u] + dep[v] - 2 * dep[LCA(u, v)];
}
int jumpfa(int u, int dis) {
    for (int i = 19; ~i; i--)
        if (dis >= (1 << i)) u = fa[u][i], dis -= (1 << i);
    return u;
}
void dfs(int u) {
    for (int i = 1; i < 20; i++) fa[u][i] = fa[fa[u][i - 1]][i - 1];
    for (int v : G[u]) {
        fa[v][0] = u;
        dep[v] = dep[u] + 1;
        dfs(v);
    }
}
int deg[400005];
bool topsort(vector<int> pt) {
    for (int x : pt) deg[x] = 0;
    for (int x : pt) {
        for (int v : G2[x]) deg[v]++;
    }
    queue<int> q;
    int cnt = 0;
    for (int x : pt) {
        if (deg[x] == 0) q.push(x);
    }
    while (!q.empty()) {
        int x = q.front();
        q.pop();
        cnt++;
        for (int v : G2[x]) {
            deg[v]--;
            if (deg[v] == 0) q.push(v);
        }
    }
    return cnt == (int)pt.size();
}
int dd[400005];
void solve() {
    cin >> n;
    for (int i = 2; i <= n; ++i) {
        int x;
        cin >> x, G[x].push_back(i);
    }
    dfs(1);
    // for (int i = 1; i <= n; ++i) cout << dep[i] << endl;
    int q;
    cin >> q;
    for (int tt = 1; tt <= q; ++tt) {
        int m;
        cin >> m;
        vector<int> a(m);
        for (int i = 0; i < m; ++i) cin >> a[i];
        bool flag = 1;
        for (int i = 1; i < m; ++i) {
            if (dep[a[i]] < dep[a[i - 1]]) flag = 0;
        }
        if (flag) {
            vector<int> vis;
            for (int i = 1; i < m; ++i) {
                int x = a[i-1], y = a[i];
                if (dep[x] != dep[y]) continue;
                if (dd[x] == tt) flag = 0;
                dd[x] = tt;
                int Lca = LCA(x, y);
                int xx = jumpfa(x, dep[x] - dep[Lca] - 1), yy = jumpfa(y, dep[y] - dep[Lca] - 1);
                // cout << xx << " " << x << " " << yy << " " << y << " " << Lca << endl;
                G2[xx].push_back(yy);
                vis.push_back(xx);
                vis.push_back(yy);
            }
            if (flag) flag = topsort(vis);
            for (int v : vis) G2[v].clear();
        }
        cout << (flag ? "Yes" : "No") << endl;
    }
}
int main() {
    ios::sync_with_stdio(false);
    int T = 1;
    while (T--) {
        solve();
    }
}

源文件, 语言: C++23

详细

Test #1:

score: 100

Accepted

time: 0ms

memory: 5664kb

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: 180ms

memory: 52664kb

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

result:

wrong answer expected YES, found NO [2nd token]