#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2")
#include<bits/stdc++.h>
using namespace std;
const int maxn=18,maxm=387420489,mod=998244353;
int pd[maxm],t[(1<<maxn)],mar;
long long mypow(long long m,long long y){
if(y==0){
return 1;
}
long long p=mypow(m,(y>>1));
p*=p;
p%=mod;
if(y&1){
p*=m;
p%=mod;
}
return p;
}
int ww(int a){
if(a>=mod){
a-=mod;
}
return a;
}
pair<int,int>tab2(int a){
int now=0;
pair<int,int>ret=make_pair(0,0);
while(a!=0){
if(a%3==1){
ret.first+=(1<<now);
}else if(a%3==2){
ret.second+=(1<<now);
}
now++;
a/=3;
}
return ret;
}
int back3(int a,int b){
int ret=t[a]+2*t[b];
return ret;
}
vector<int>tartib[maxn];
int adj[maxn],adja[maxn];
int n,m;
void aval(){
mar=(1<<n)-1;
int nx=1;
for(int i=0;i<(1<<n);i++){
int now=1,ret=0;
for(int j=0;j<n;j++){
if((i>>j)&1){
ret+=now;
}
now*=3;
}
t[i]=ret;
tartib[__builtin_popcount(i)].push_back(i);
}
}
void solve(){
for(int i=0;i<maxn;i++){
for(auto xx:tartib[i]){
for(int y=(mar^xx);y>0;y=(-y)&(mar^xx)){
int x=back3(xx,y);
if(pd[x]==0){
continue;
}
pair<int,int>now=tab2(x);
for(int j=0;j<n;j++){
if((now.second>>j)&1){
now.second^=(1<<j);
pair<int,int>fake=now;
fake.first|=(1<<j);
fake.second|=(adj[j]^(adj[j]&now.first));
int tof=back3(fake.first,fake.second);
pd[tof]+=pd[x];
pd[tof]=ww(pd[tof]);
}
}
}
}
}
}
int main(){
ios::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
cin>>n>>m;
aval();
if(n>15){
return 0;
}
for(int i=0;i<m;i++){
int u,v;
cin>>u>>v;
u--;
v--;
adj[u]|=(1<<v);
adj[v]|=(1<<u);
adja[u]|=(1<<v);
}
pd[back3(0,(1<<n)-1)]=1;
solve();
int res=back3((1<<n)-1,0);
pd[res]=1ll*pd[res]*m%mod;
pd[res]=1ll*pd[res]*mypow(2,mod-2)%mod;
cout<<pd[res]<<"\n";
}
Compilation message
amusementpark.cpp: In function 'void aval()':
amusementpark.cpp:53:6: warning: unused variable 'nx' [-Wunused-variable]
53 | int nx=1;
| ^~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Execution timed out |
3013 ms |
2392 KB |
Time limit exceeded |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Execution timed out |
3013 ms |
2392 KB |
Time limit exceeded |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Execution timed out |
3013 ms |
2392 KB |
Time limit exceeded |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Execution timed out |
3013 ms |
2392 KB |
Time limit exceeded |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Execution timed out |
3013 ms |
2392 KB |
Time limit exceeded |
| 2 |
Halted |
0 ms |
0 KB |
- |
