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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 |
---|---|---|---|---|---|---|---|---|---|
#416602 | #8720. BFS 序 0 | Afterlife# | WA | 560ms | 814084kb | C++17 | 3.5kb | 2024-05-21 23:54:02 | 2024-05-21 23:54:04 |
Judging History
answer
#include<bits/stdc++.h>
using namespace std;
const int N=1e6+1e3+7;
int n,st[N],ed[N],dep[N],dc;
vector<int> g[N];
int anc[N][21];
void dfs(int x,int f)
{
st[x]=++dc;
anc[x][0]=f;
for(int j=1;j<=20;j++)
anc[x][j]=anc[anc[x][j-1]][j-1];
for(auto v:g[x])
{
if(v==f)
continue;
dep[v]=dep[x]+1;
dfs(v,x);
}
ed[x]=dc;
}
int lca(int x,int y)
{
if(dep[x]<dep[y])
swap(x,y);
for(int i=20;i>=0;i--)
if(dep[x]-(1<<i)>=dep[y])
x=anc[x][i];
if(x==y)
return x;
for(int i=20;i>=0;i--)
if(anc[x][i]!=anc[y][i])
x=anc[x][i],y=anc[y][i];
return anc[x][0];
}
namespace SOLVE {
int m, i, a[N], q[N], t, tot;
int pos[N];
void dfs(int x)
{
for(auto v:g[x])
dfs(v),pos[x]=min(pos[x],pos[v]);
}
bool vip[N], vis[N];
bool cmp(int x, int y) { return st[x] < st[y]; }
vector<int> g[N];
queue<int> Q[N];
vector<int> h[N];
int deg[N];
void solve(vector<int> v,vector<int> seq) {
int la=-1;
bool ok=1;
for(auto x:seq)
{
if(dep[x]<la)
ok=0;
la=dep[x];
}
if(!ok)
{
cout<<"No\n";
return;
}
if (!v.size())
return;
vis[1] = vip[1] = a[1] = 1;
m = v.size();
for (tot = ++m, i = 2; i <= m; i++)
a[i] = v.back(), v.pop_back(), vis[a[i]] = vip[a[i]] = 1;
sort(a + 1, a + m + 1, cmp);
int x;
for (i = 1; i < m; i++)
if (!vis[x = lca(a[i], a[i + 1])])
vis[a[++tot] = x] = 1;
vector<int> use;
m = tot, sort(a + 1, a + m + 1, cmp);
for (q[t = 1] = 1, i = 2; i <= m; q[++t] = a[i++]) {
while (st[a[i]] < st[q[t]] || ed[a[i]] > ed[q[t]]) // dfs order
t--;
if (q[t] != a[i])
g[q[t]].push_back(a[i]);
use.push_back(q[t]);
use.push_back(a[i]);
}
sort(use.begin(),use.end());
use.erase(unique(use.begin(),use.end()),use.end());
for(auto x:use)
h[x].clear(),h[x+n].clear(),deg[x]=0,deg[x+n]=0;
for(auto x:use)
{
h[x+n].push_back(x);
++deg[x];
for(auto y:g[x])
{
h[y].push_back(x);
++deg[x];
h[x+n].push_back(y+n);
++deg[y+n];
}
}
for(int i=0;i+1<seq.size();i++)
{
int x=seq[i],y=seq[i+1];
if(dep[x]!=dep[y])
continue;
h[x].push_back(y+n);
++deg[y+n];
}
queue<int> q;
for(auto x:use)
{
if(!deg[x])
q.push(x);
if(!deg[x+n])
q.push(x+n);
}
int cnt=0;
while(!q.empty())
{
int x=q.front();
q.pop();
++cnt;
for(auto v:h[x])
if(!--deg[v])
q.push(v);
}
ok&=cnt==use.size()*2;
if(ok)
cout<<"Yes\n";
else
cout<<"No\n";
for (auto x : use)
vis[x] = vip[x] = 0, g[x].clear();
return;
}
} // namespace SOLVE
int main()
{
ios::sync_with_stdio(false);
cin.tie(0);
cin>>n;
for(int i=2;i<=n;i++)
{
int f;
cin>>f;
g[f].push_back(i);
}
dfs(1,0);
int m;
cin>>m;
while(m--)
{
int k;
cin>>k;
vector<int> s;
while(k--)
{
int x;
cin>>x;
s.push_back(x);
}
SOLVE::solve(s,s);
}
}
詳細信息
Test #1:
score: 100
Accepted
time: 132ms
memory: 759736kb
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: 560ms
memory: 814084kb
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 Yes No No ...
result:
wrong answer expected NO, found YES [87th token]