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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
#424723#8720. BFS 序 0_mjjWA 201ms81984kbC++203.4kb2024-05-29 16:15:042024-05-29 16:15:04

Judging History

你现在查看的是最新测评结果

  • [2024-05-29 16:15:04]
  • 评测
  • 测评结果:WA
  • 用时:201ms
  • 内存:81984kb
  • [2024-05-29 16:15:04]
  • 提交

answer

#include <bits/stdc++.h>
#define x first
#define y second
#define all(v) v.begin() , v.end()
#define ios ios::sync_with_stdio(false), cin.tie(0), cout.tie(0);
#define int long long

using namespace std;

typedef long long LL;
typedef pair<int , int> PII;

const int N = 3e5 + 5;
const int mod = 998244353;
const int INF = 0x3f3f3f3f;

vector<int> q[N];
int d[N];
vector<int> e[N];
int in[N];

void dfs(int u , int fa){
    d[u] = d[fa] + 1;
    for(auto c : q[u]){
        if(c == fa)continue;
        dfs(c , u);
    }
}

int qq[N] , depth[N];
int fa[N][20];

void bfs(int root){
    memset(depth , 0x3f , sizeof depth);
    depth[0] = 0 , depth[root] = 1;
    qq[0] = root;
    int tt = 0 , hh = 0;
    while(hh <= tt){
        int t = qq[hh ++];
        for(auto c : q[t]){
            int j = c;
            if(depth[j] > depth[t] + 1){
                depth[j] = depth[t] + 1;
                qq[++ tt] = j;
                fa[j][0] = t;
                for(int k = 1 ; k <= 19 ; k ++)
                    fa[j][k] = fa[fa[j][k - 1]][k - 1];
            }
        }
    }
}

int lca(int a , int b){
    if(depth[a] < depth[b])swap(a , b);
    for(int k = 19 ; k >= 0 ; k --)
        if(depth[fa[a][k]] >= depth[b])
            a = fa[a][k];
    if(a == b)return a;
    for(int k = 19 ; k >= 0 ; k --)
        if(fa[a][k] != fa[b][k]){
            a = fa[a][k];
            b = fa[b][k];
        }
    return fa[a][0];
}

int get(int a , int b){
    for(int i = 19 ; i >= 0 ; i --){
        if(d[fa[a][i]] > d[b]){
            a = fa[a][i];
        }
    }
    return a;
}

void solve(){
    int n;
    cin >> n;
    for(int i = 1 ; i < n ; i ++){
        int x;
        cin >> x;
        q[x].push_back(i + 1);
    }
    dfs(1 , 0);
    bfs(1);
    int q;
    cin >> q;
    while(q --){
        int m;
        cin >> m;
        vector<int> ss;
        bool ok = 1;
        for(int i = 1 ; i <= m ; i ++){
            int x;
            cin >> x;
            ss.push_back(x);
        }
        int mx = 0;
        for(auto c : ss){
            if(d[c] < mx)ok = 0;
            mx = max(mx , d[c]);
        }
        if(!ok){
            cout << "No\n";
            for(int i = 0 ; i < m ; i ++)e[ss[i]].clear() , in[ss[i]] = 0;
            continue;
        }
        for(int i = 0 ; i < m ; i ++){
            int j = i;
            while(j + 1 < m && d[j + 1] == d[i])j ++;
            for(int k = i ; k < j ; k ++){
                int t = lca(ss[k] , ss[k + 1]);
                int u = get(ss[k] , t) , v = get(ss[k + 1] , t);
                e[u].push_back(v);
                in[v] ++;
            }
            i = j;
        }
        queue<int> qq;
        for(int i = 0 ; i < m ; i ++){
            if(in[ss[i]] == 0)qq.push(ss[i]);
        }
        while(qq.size()){
            auto t = qq.front();
            qq.pop();
            for(auto c : e[t]){
                in[c] --;
                if(in[c] == 0){
                    qq.push(c);
                }
            }
        }
        for(int i = 0 ; i < m ; i ++){
            if(in[ss[i]])ok = 0;
        }
        if(!ok)cout << "No\n";
        else cout << "Yes\n";
        for(int i = 0 ; i < m ; i ++)e[ss[i]].clear() , in[ss[i]] = 0;
    }
}

signed main(){
    ios;
    int T = 1;
    // cin >> T;
    while(T --){
        solve();
    }
    return 0;
}

详细

Test #1:

score: 100
Accepted
time: 2ms
memory: 9772kb

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: 201ms
memory: 81984kb

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:

Yes
No
No
No
Yes
Yes
Yes
Yes
Yes
Yes
No
No
Yes
No
Yes
Yes
Yes
No
Yes
Yes
Yes
Yes
No
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
Yes
No
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
Yes
Yes
Yes
No
Yes
No
Yes
Yes
No
No
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
Yes
No
Yes
Yes
Yes
No
Yes
Yes
No
No
Yes
Yes
Yes
Yes
Yes
Yes
No
Yes
N...

result:

wrong answer expected NO, found YES [1st token]