#include <bits/stdc++.h>
using namespace std;
#define int long long
#define double long double
#define FOR(i, l, r, d) for(int i=(l); i<=(r); i+=(d))
#define szof(x) ((int)(x).size())
#define vi vector<int>
#define pii pair<int, int>
#define F first
#define S second
#define pb push_back
#define eb emplace_back
#define mkp make_pair
const int INF = 2147483647;
const int LNF = INF*INF;
const int MOD = 1000000007;
const int mod = 998244353;
const double eps = 1e-12;
//#pragma GCC optimize("Ofast")
//#pragma GCC optimize("unroll-loops")
const int MAX = 270000;
const int inv2 = (mod + 1) / 2;
int n, m;
bool edge[18][18];
int Nc[18];
int sz;
unordered_map<int, int> dp[MAX];
signed main(){
ios_base::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
cin>>n>>m;
sz = (1<<n);
FOR(i, 1, m, 1){
int u, v;
cin>>u>>v;
u--, v--;
edge[u][v] = edge[v][u] = 1;
}
FOR(i, 0, n-1, 1){
FOR(j, 0, n-1, 1){
if(edge[i][j]) Nc[i] |= (1<<j);
}
}
FOR(v, 0, n-1, 1){
dp[(1<<v)][sz - 1 - (1<<v)] = 1;
}
FOR(A, 1, sz-1, 1){
int IA = sz - 1 - A;
for(int B = IA; B > 0; B = ((B-1) & IA)){
dp[A][B] += 0;
int AA, BB;
// AA = A U {c};
// BB = B \ {0, ..., c-1} U {N(c) \ A}
//cerr<<"dp["<<A<<"]["<<B<<"] = "<<dp[A][B]<<endl;
FOR(c, 0, n-1, 1){
if((B & (1<<c)) == 0) continue;
AA = A | (1<<c);
BB = B & (~(1<<c));
BB |= (Nc[c] & (~A));
dp[AA][BB] += dp[A][B];
dp[AA][BB] %= mod;
//cerr<<"dp["<<AA<<"]["<<BB<<"] += "<<dp[A][B]<<endl;
}
}
}
//cerr<<"ways = "<<dp[sz-1][0]<<endl;
int res = (dp[sz-1][0] * ((m * inv2) % mod)) % mod;
cout<<res<<'\n';
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
9 ms |
15016 KB |
Output is correct |
2 |
Correct |
9 ms |
14988 KB |
Output is correct |
3 |
Incorrect |
8 ms |
15108 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
9 ms |
15016 KB |
Output is correct |
2 |
Correct |
9 ms |
14988 KB |
Output is correct |
3 |
Incorrect |
8 ms |
15108 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
9 ms |
15016 KB |
Output is correct |
2 |
Correct |
9 ms |
14988 KB |
Output is correct |
3 |
Incorrect |
8 ms |
15108 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
9 ms |
15016 KB |
Output is correct |
2 |
Correct |
9 ms |
14988 KB |
Output is correct |
3 |
Incorrect |
8 ms |
15108 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
9 ms |
15016 KB |
Output is correct |
2 |
Correct |
9 ms |
14988 KB |
Output is correct |
3 |
Incorrect |
8 ms |
15108 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |