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QOJ
| 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 |
|---|---|---|---|---|---|---|---|---|---|
| #106354 | #5307. Subgraph Isomorphism | qinsanma | WA | 120ms | 22520kb | C++14 | 5.2kb | 2023-05-17 15:14:14 | 2023-10-15 17:25:07 |
Judging History
answer
#include <bits/stdc++.h>
using namespace std;
typedef long long int ll;
typedef unsigned long long ull;
const ull mask = std::chrono::steady_clock::now().time_since_epoch().count();
typedef pair<ull,ull> HASH ;
vector<int>v[500000+10];
int du[500000+10],vis[500000+10];
queue<int>q;
int nowzhong[2],nown,fuck;
int sizeson[500000+10],maxx[500000+10];
void getzhong(int now,int pre)
{
for(auto it:v[now])
{
if(it==pre)
continue;
if(it==fuck||vis[it]==1)
{
getzhong(it,now);
maxx[now]=max(maxx[now],sizeson[it]);
}
}
maxx[now]=max(maxx[now],nown-sizeson[now]);
// cout<<maxx[now]<<" ---- "<<endl;
if(maxx[now]<=nown/2)
{
if(nowzhong[0]==0)
{
nowzhong[0]=now;
}
else
{
nowzhong[1]=now;
}
}
}
void dfs(int now,int pre)
{
sizeson[now]++;
for(auto it:v[now])
{
if(it==pre)
continue;
if(it==fuck||vis[it]==1)
{
dfs(it,now);
sizeson[now]+=sizeson[it];
}
}
}
ull shift(ull x)
{
x^=mask;
x^=x<<13;
x^=x>>7;
x^=x<<17;
x^=mask;
return x;
}
ull gethash(int now,int pre)
{
// cout<<now<<endl;
ull nowhash=1;
for(auto it:v[now])
{
if(it==pre)
continue;
if(it==fuck||(vis[it]==1))
{
nowhash+=shift(gethash(it,now));
}
}
return nowhash;
}
vector<HASH>ans;
void work(int root)
{
//cout<<"work" <<" "<<root<<endl;
fuck=root;
dfs(root,0);
// cout<<"dfs";
nown=sizeson[root];
nowzhong[0]=nowzhong[1]=0;
getzhong(root,0);
// cout<<"getzhong";
// cout<<nowzhong[0]<<" "<<nowzhong[1]<<" === "<<endl;
HASH temp;
temp.first=gethash(nowzhong[0],0);
// cout<<temp.first<<endl;
if(nowzhong[1])
{
temp.second=gethash(nowzhong[1],0);
if(temp.first<temp.second)
swap(temp.first,temp.second);
}
else
temp.second=temp.first;
ans.push_back(temp);
}
int main()
{
//先求树的重心
int t;
cin>>t;
//5 5
/*
1 4
1 5
2 5
3 5
4 5
*/
int fuckcnt=0;
while(t--)
{
int n,m;
cin>>n>>m;
for(int i=1; i<=n; i++)
{
v[i].clear();
du[i]=0;
vis[i]=0;
sizeson[i]=0;
maxx[i]=0;
}
ans.clear();
while(!q.empty())
q.pop();
for(int i=1; i<=m; i++)
{
int x,y;
cin>>x>>y;
v[x].push_back(y);
v[y].push_back(x);
du[x]++;
du[y]++;
}
if(m==n-1)
{
cout<<"YES"<<endl;
}
else if(m>n)
{
cout<<"NO"<<endl;
}
else
{
//必有环
for(int i=1; i<=n; i++)
{
if(du[i]==1)
{
q.push(i);
vis[i]=1;
}
}
int cnt=n;
while(!q.empty())
{
int now=q.front();
q.pop();
vis[now]=1;
cnt--;
for(auto it:v[now])
{
du[it]--;
if(du[it]==1)
q.push(it);
}
}
int root=0;
for(int i=1; i<=n; i++)
{
if(vis[i]==0)
{
root=i;
vis[root]=2;
break;
}
}
// cout<<cnt<<endl;
for(int i=1; i<=cnt; i++)
{
// cout<<root<<" ";
// cout<<i<<endl;
work(root);
for(auto it:v[root])
{
if(vis[it]==0)
{
root=it;
vis[it]=2;
break;
}
}
}
HASH pre=ans[0];
int flag=0;
for(auto it:ans)
{
if(it!=pre)
{
flag=1;
}
//cout<<it.first<<" "<<it.second<<endl;
}
if(!flag)
{
cout<<"YES"<<endl;
}
else
{
flag=0;
for(int i=0; i<ans.size(); i++)
{
if(ans[(i+2)%(int)(ans.size())]!=ans[i])
{
flag=1;
}
}
if(flag)
{
cout<<"NO"<<endl;
}
else
{
cout<<"YES"<<endl;
}
}
}
}
return 0;
}
详细
Test #1:
score: 100
Accepted
time: 0ms
memory: 22120kb
input:
4 7 6 1 2 2 3 3 4 4 5 5 6 3 7 3 3 1 2 2 3 3 1 5 5 1 2 2 3 3 4 4 1 1 5 1 0
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: 120ms
memory: 22520kb
input:
33192 2 1 1 2 3 2 1 3 2 3 3 3 1 2 1 3 2 3 4 3 1 4 2 4 3 4 4 3 1 3 1 4 2 4 4 4 1 3 1 4 2 4 3 4 4 4 1 3 1 4 2 3 2 4 4 5 1 3 1 4 2 3 2 4 3 4 4 6 1 2 1 3 1 4 2 3 2 4 3 4 5 4 1 5 2 5 3 5 4 5 5 4 1 4 1 5 2 5 3 5 5 5 1 4 1 5 2 5 3 5 4 5 5 5 1 4 1 5 2 4 3 5 4 5 5 5 1 4 1 5 2 4 2 5 3 5 5 6 1 4 1 5 2 4 2 5 3 ...
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 YES 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 NO, found YES [1085th token]