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ID	Problem	Submitter	Result	Time	Memory	Language	File size	Submit time	Judge time
#602625	#8720. BFS 序 0	ucup-team902^#	WA	191ms	50980kb	C++23	2.6kb	2024-10-01 11:20:07	2024-10-01 11:20:09

Judging History

你现在查看的是最新测评结果

[2024-10-01 11:20:09]
评测

测评结果：WA
用时：191ms
内存：50980kb

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[2024-10-01 11:20:07]
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();
}
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;
    while (q--) {
        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], y = a[i - 1];
                if (dep[x] != dep[y]) continue;
                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);
            }
            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();
    }
}

Source code, Language: C++23

Details

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Test #1:

score: 100

Accepted

time: 2ms

memory: 3780kb

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: 191ms

memory: 50980kb

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]