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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
#416202	#8720. BFS 序 0	wwxyy2005	WA	85ms	36756kb	C++14	1.8kb	2024-05-21 17:32:53	2024-05-21 17:32:53

Judging History

你现在查看的是最新测评结果

[2024-05-21 17:32:53]
评测

测评结果：WA
用时：85ms
内存：36756kb

查看

[2024-05-21 17:32:53]
提交

answer

#include <bits/stdc++.h>
using namespace std;
const int N = 3e5 + 10;
int n, q, dep[N], fa[20][N], head[N], cnt, m, a[N];
int top, id[N], in[N];
struct Edge{
	int to, nxt;
}edge[N << 1];
void add(int u, int v){
	edge[++cnt] = (Edge){v, head[u]};
	head[u] = cnt;
}
void dfs(int now, int father, int deep){
	dep[now] = deep;
	for(int i = head[now]; i; i = edge[i].nxt){
		if(edge[i].to == father) continue;
		dfs(edge[i].to, now, deep + 1);
	}
}
queue<int> st;
int main()
{
	ios::sync_with_stdio(0);
	cin >> n;
	for(int i = 2; i <= n; ++i) cin >> fa[0][i], add(fa[0][i], i);
	dfs(1, 0, 1);
	for(int j = 1; j <= 19; ++j)
		for(int i = 1; i <= n; ++i) fa[j][i] = fa[j - 1][fa[j - 1][i]];
	memset(head, 0, sizeof(head));
	cin >> q;
	while(q--){
		cin >> m;
		for(int i = 1; i <= m; ++i) cin >> a[i];
		bool flag = true;
		for(int i = 1; i < m; ++i){
			if(dep[a[i]] > dep[a[i + 1]]){flag = false; break;}
		}
		if(!flag){
			cout << "No" << endl;
			continue;
		}
		for(int i = 1; i < m; ++i){
			if(dep[a[i]] != dep[a[i + 1]]) continue;
			int u = a[i], v = a[i + 1];
			for(int j = 19; j >= 0; --j) if(fa[j][u] != fa[j][v]) u = fa[j][u], v = fa[j][v];
			add(u, v);
			id[++top] = u, id[++top] = v; in[v]++;
		}
		top = unique(id + 1, id + 1 + top) - id - 1;
		for(int i = 1; i <= top; ++i) if(!in[id[i]]) st.push(id[i]);
		while(!st.empty()){
			int now = st.front();
			st.pop();
			for(int i = head[now]; i; i = edge[i].nxt){
				in[edge[i].to]--;
				if(!in[edge[i].to]) st.push(edge[i].to);
			}
		}
		for(int i = 1; i <= top; ++i) if(in[id[i]]){flag = false; break;}
		if(flag) cout << "Yes" << endl;
		else cout << "No" << endl;
		for(int i = 1; i <= top; ++i) in[id[i]] = 0, head[id[i]] = 0;
		top = 0, cnt = 0;
	}
	return 0;
}

源文件, 语言: C++14

详细

Test #1:

score: 100

Accepted

time: 2ms

memory: 30356kb

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: 85ms

memory: 36756kb

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

result:

wrong answer expected YES, found NO [3rd token]