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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
#602856#8720. BFS 序 0UESTC_DECAYALI#WA 168ms46212kbC++202.6kb2024-10-01 13:11:042024-10-01 13:11:06

Judging History

你现在查看的是最新测评结果

  • [2024-10-01 13:11:06]
  • 评测
  • 测评结果:WA
  • 用时:168ms
  • 内存:46212kb
  • [2024-10-01 13:11:04]
  • 提交

answer

#include <bits/stdc++.h>

std::vector <int> G[300005];
int deg[300005];

void work() {
    int n; std::cin >> n;
    std::vector<int> pa(n, 0);
    std::vector<std::vector<int>> ch(n), loop(n);
    std::vector<int> dfn(n), dep(n);
    for(int i = 1; i < n; ++i) std::cin >> pa[i], pa[i]--, ch[pa[i]].emplace_back(i);

    int O = 0;
    auto dfs = [&](auto dfs, int cur) -> void {
        dfn[cur] = O++;
        loop[cur].emplace_back(pa[cur]);
        while(loop[cur].back() == 0) {
            if(loop[loop[cur].back()].size() <= loop[cur].size()) break;
            loop[cur].emplace_back(loop[loop[cur].back()][loop[cur].size() - 1]);
        }
        for(auto ch: ch[cur]) dep[ch] = dep[cur] + 1, dfs(dfs, ch);
    };

    auto lca = [&](int a, int b) -> int {
        if(dep[a] < dep[b]) std::swap(a, b);
        for(int i = 20; ~i; --i) if((dep[a] - dep[b]) & (1 << i)) a = loop[a][i];
        if(a == b) return a;
        for(int i = 20; ~i; --i) if(loop[a].size() > i && loop[a][i] != loop[b][i])
            a = loop[a][i], b = loop[b][i];
        return loop[a][0];
    };

    auto jump = [&](int &x, int step) {
        assert(dep[x] >= step);
        for (int i=20;i>=0;--i) if ((step>>i)&1) x=loop[x][i];
    };

    dep[0] = 0;
    dfs(dfs, 0);

    int q; std::cin >> q;

    auto query = [&]() -> bool {
        int m; std::cin >> m;
        std::vector<int> b(m);
        for(auto &b: b) std::cin >> b, b--;
        std::vector <int> ext;
        for (int i=0;i+1<m;++i)
        if (dep[b[i+1]]<dep[b[i]]||b[i]==b[i+1]) return false;
        for (int i=0;i+1<m;++i)
        {
            int x=b[i],y=b[i+1];
            if (dep[x]!=dep[y]) continue;
            int z=lca(x,y);
            jump(x,dep[x]-dep[z]-1); jump(y,dep[y]-dep[z]-1);
            ext.push_back(x); ext.push_back(y);
            G[x].push_back(y); ++deg[y];
        }
        std::sort(ext.begin(),ext.end());
        ext.erase(std::unique(ext.begin(),ext.end()),ext.end());
        std::queue <int> Q; int cnt=0;
        for (auto x:ext) if (!deg[x]) Q.push(x),++cnt;
        while (!Q.empty())
        {
            int now=Q.front(); Q.pop();
            for (auto to:G[now])
            if (!--deg[to]) Q.push(to),++cnt;
        }
        for (auto x:ext) G[x].clear(),deg[x]=0;
        return cnt==(int)ext.size();
    };

    while(q--) std::cout << (query() ? "Yes\n" : "No\n");
    return ;
}

int main() {
    // freopen("H.in","r",stdin);
    std::ios::sync_with_stdio(false);
    int T = 1; while(T--) work();
    return 0;
}

详细

Test #1:

score: 100
Accepted
time: 1ms
memory: 3796kb

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: 168ms
memory: 46212kb

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
Yes
Yes
No
No
No
No
No
No
Yes
Yes
No
Yes
No
Yes
Yes
Yes
No
No
No
No
Yes
No
No
Yes
No
No
No
No
Yes
Yes
Yes
No
No
Yes
No
No
No
No
No
No
No
Yes
No
Yes
No
Yes
No
No
No
No
Yes
Yes
Yes
No
No
Yes
No
No
No
No
No
Yes
Yes
No
No
No
No
No
Yes
Yes
No
Yes
No
No
No
Yes
No
No
Yes
No
No
Yes
Yes
Yes
No
No
No
Y...

result:

wrong answer expected NO, found YES [176th token]