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ID	Problem	Submitter	Result	Time	Memory	Language	File size	Submit time	Judge time
#219636	#5307. Subgraph Isomorphism	isaunoya	WA	1ms	5900kb	C++23	2.2kb	2023-10-19 16:56:58	2023-10-19 16:56:58

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[2023-10-19 16:56:58]
评测

测评结果：WA
用时：1ms
内存：5900kb

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[2023-10-19 16:56:58]
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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 mask=std::chrono::steady_clock::now().time_since_epoch().count();
const unsigned long long S=1;
unsigned long long shift(unsigned long long x)
{
  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;
}
int t=0;
void solve()
{
  t++;
  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(t==39) cout<<n<<","<<m,exit(0);
  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);
      deg[i]--;
      break;
    }
  while(!q.empty())
  {
    int u=q.front();
    q.pop();
    pos.emplace_back(u);
    for(int v:G[u])
    {
      deg[v]--;
      if(deg[v]==1) q.emplace(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;
}

Source code, Language: C++23

Details

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Test #1:

score: 100

Accepted

time: 1ms

memory: 5836kb

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: 1ms

memory: 5900kb

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
6,6

result:

wrong output format YES or NO expected, but 6,6 found [39th token]