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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
#219614	#5307. Subgraph Isomorphism	isaunoya	WA	64ms	5920kb	C++23	2.2kb	2023-10-19 16:46:47	2023-10-19 16:46:48

Judging History

你现在查看的是最新测评结果

[2023-10-19 16:46:48]
评测

测评结果：WA
用时：64ms
内存：5920kb

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[2023-10-19 16:46:47]
提交

answer

#include<iostream>
#include<cstdio>
#include<vector>
#include<random>
#include<chrono>
#include<queue>
#include<map>
using namespace std;
const int N=100005;
const unsigned long long S=1;
unsigned long long shift(unsigned long long x)
{
  static const unsigned long long mask=std::chrono::steady_clock::now().time_since_epoch().count();
  x^=mask;
  x^=x<<13;
  x^=x>>7;
  x^=x<<17;
  x^=mask;
  return x;
}
int n,m;
vector<int>G[N];
int deg[N];
bool vis[N];
unsigned long long f[N];
void dfs(int u)
{
  f[u]=S;
  vis[u]=true;
  for(int v:G[u])
  {
    if(vis[v]) continue;
    dfs(v);
    f[u]+=shift(f[v]);
  }
  return;
}
void solve()
{
  cin>>n>>m;
  for(int i=1;i<=n;i++)
    G[i].clear(),deg[i]=0;
  map<pair<int,int>,bool>book;
  for(int i=1;i<=m;i++)
  {
    int x,y;
    cin>>x>>y;
    if(book.count({x,y})) continue;
    book[{x,y}]=true;
    G[x].emplace_back(y);
    G[y].emplace_back(x);
    deg[x]++,deg[y]++;
  }
  if(m==n-1)
  {
    cout<<"YES\n";
    return;
  }
  if(m>n)
  {
    cout<<"NO\n";
    return;
  }
  queue<int>q;
  for(int i=1;i<=n;i++)
    if(deg[i]==1) q.emplace(i);
  while(!q.empty())
  {
    int u=q.front();
    q.pop();
    for(int v:G[u])
    {
      deg[v]--;
      if(deg[v]==1) q.emplace(v);
    }
  }
  for(int i=1;i<=n;i++)
    if(deg[i]==2) vis[i]=true;
    else vis[i]=false;
  for(int i=1;i<=n;i++)
    if(deg[i]==2) dfs(i);
  vector<int>pos;
  for(int i=1;i<=n;i++)
    if(deg[i]==2)
    {
      q.emplace(i);
      break;
    }
  while(!q.empty())
  {
    int u=q.front();
    q.pop();
    for(int v:G[u])
    {
      deg[v]--;
      if(deg[v]==1) q.emplace(v),pos.emplace_back(v);
    }
  }
  int l=pos.size();
  bool all_same=true;
  for(int i=1;i<l;i++)
    if(f[pos[i]]!=f[pos[i-1]])
    {
      all_same=false;
      break;
    }
  bool gap_same=false;
  if(l%2==0)
  {
    gap_same=true;
    for(int i=2;i<l;i++)
      if(f[pos[i]]!=f[pos[i-2]])
      {
        gap_same=false;
        break;
      }
  }
  if(all_same||gap_same) cout<<"YES\n";
  else cout<<"NO\n";
  return;
}
int main()
{
  ios::sync_with_stdio(false);
  cin.tie(nullptr),cout.tie(nullptr);
  int T;
  cin>>T;
  while(T--)
    solve();
  return 0;
}

源文件, 语言: C++23

詳細信息

Test #1:

score: 100

Accepted

time: 1ms

memory: 5912kb

input:

output:

YES
YES
NO
YES

result:

ok 4 token(s): yes count is 3, no count is 1

Test #2:

score: -100

Wrong Answer

time: 64ms

memory: 5920kb

input:

output:

YES
YES
YES
YES
YES
NO
YES
NO
NO
YES
YES
NO
NO
NO
NO
NO
NO
YES
NO
NO
NO
NO
YES
NO
NO
NO
NO
NO
NO
NO
YES
YES
NO
YES
YES
NO
NO
NO
NO
NO
NO
NO
NO
NO
YES
NO
NO
NO
YES
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
YES
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
YES
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
...

result:

wrong answer expected YES, found NO [39th token]