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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
#219606	#5307. Subgraph Isomorphism	isaunoya	WA	37ms	5860kb	C++23	2.1kb	2023-10-19 16:39:41	2023-10-19 16:39:42

Judging History

你现在查看的是最新测评结果

[2023-10-19 16:39:42]
评测

测评结果：WA
用时：37ms
内存：5860kb

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[2023-10-19 16:39:41]
提交

answer

#include<iostream>
#include<cstdio>
#include<vector>
#include<random>
#include<chrono>
#include<queue>
using namespace std;
const unsigned long long S=1;
const int N=100005;
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;
  for(int i=1;i<=m;i++)
  {
    int x,y;
    cin>>x>>y;
    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]==0) 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

详细

Test #1:

score: 100

Accepted

time: 2ms

memory: 5860kb

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: 37ms

memory: 5860kb

input:

output:

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

result:

wrong answer expected NO, found YES [13th token]