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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
#795678	#8720. BFS 序 0	Calculatelove	WA	107ms	52564kb	C++14	2.8kb	2024-11-30 23:05:44	2024-11-30 23:05:44

Judging History

This is the latest submission verdict.

[2024-11-30 23:05:44]
Judged

Verdict: WA
Time: 107ms
Memory: 52564kb

Show

[2024-11-30 23:05:44]
Submitted

answer

#include <bits/stdc++.h>

const int N = 500100;

int n, Q;

int dep[N];
int anc[19][N];

int lca(int x, int y) {
    if (dep[x] > dep[y]) std::swap(dep[x], dep[y]);
    for (int i = 18; i >= 0; i --)
        if (dep[x] <= dep[y] - (1 << i)) y = anc[i][y];
    if (x == y) return x;
    for (int i = 18; i >= 0; i --)
        if (anc[i][x] ^ anc[i][y]) x = anc[i][x], y = anc[i][y];
    return anc[0][x];
}

int jump(int x, int y) {
    for (int i = 18; i >= 0; i --)
        if (dep[anc[i][x]] > dep[y]) x = anc[i][x];
    return x;
}

int m, seq[N];

bool exist[N];
int crulen, cru[N];

bool insert(int x) {
    if (exist[x]) {
        return 0;
    } else {
        exist[x] = 1, cru[++ crulen] = x;
        return 1;
    }
}

int tot, head[N], ver[N * 2], Next[N * 2], deg[N];
void add_edge(int u, int v) {
    ver[++ tot] = v;    Next[tot] = head[u];    head[u] = tot;    deg[v] ++;
}

int main() {
    scanf("%d", &n);

    for (int i = 2; i <= n; i ++)
        scanf("%d", &anc[0][i]), dep[i] = dep[anc[0][i]] + 1;
    
    for (int j = 1; j <= 18; j ++)
        for (int i = 1; i <= n; i ++)
            anc[j][i] = anc[j - 1][anc[j - 1][i]];

    scanf("%d", &Q);

    while (Q --) {
        tot = 0;
        for (int i = 1; i <= crulen; i ++) exist[cru[i]] = 0, head[cru[i]] = 0, deg[cru[i]] = 0;
        crulen = 0;

        scanf("%d", &m);

        for (int i = 1; i <= m; i ++)
            scanf("%d", &seq[i]);
        
        bool flag = 1;

        for (int i = 1; i <= m; i ++)
            if (!insert(seq[i])) flag = 0;
        
        if (!flag) {
            puts("No");
            continue;
        }

        int d = dep[seq[1]];
        for (int i = 2; i <= m; i ++)
            if (d <= dep[seq[i]]) d = dep[seq[i]];
            else flag = 0;

        if (!flag) {
            puts("No");
            continue;
        }

        for (int st = 1, ed; st <= m; st = ed + 1) {
            ed = st;
            while (ed < m && dep[seq[ed + 1]] == dep[seq[ed]]) ed ++;

            for (int i = st; i < ed; i ++) {
                int x = seq[i], y = seq[i + 1], z = lca(x, y);
                int fx = jump(x, dep[x] - dep[z] - 1), fy = jump(y, dep[y] - dep[z] - 1);

                insert(fx), insert(fy);
                add_edge(fx, fy);
            }
        }

        std::queue<int> q;
        for (int i = 1; i <= crulen; i ++)
            if (deg[cru[i]] == 0) q.push(cru[i]);
        
        int t = 0;
        while (q.size()) {
            int u = q.front(); q.pop();
            t ++;

            for (int i = head[u]; i; i = Next[i]) {
                int v = ver[i];
                if (-- deg[v] == 0) q.push(v);
            }
        }

        puts(t == crulen ? "Yes" : "No");
    }

    return 0;
}

源文件, 语言: C++14

詳細信息

Test #1:

score: 100

Accepted

time: 0ms

memory: 48696kb

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: 107ms

memory: 52564kb

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

result:

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