//Be Name KHODA
#pragma GCC optimize("Ofast")
#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
#define pb push_back
#define pp pop_back
#define cl clear
#define bg begin
#define lb lower_bound
#define ub upper_bound
#define arr(x) array<int , x>
#define endl '\n'
const int MOD = 998244353;
int n , m;
int g[18][18] , inf[18];
int dp[18][(1 << 18)][2];
int Sum(int a , int b){
int res = a + b;
if(res > MOD) return res - MOD;
if(res < 0) return res + MOD;
return res;
}
void Add(int &a , int b){
a += b;
if(a > MOD) a -= MOD;
if(a < 0) a += MOD;
}
int Mul(int a , int b){
return (1ll * a * b) % MOD;
}
void f(){
for(int b = 0 ; b < n ; b++) dp[b][0][0] = 1;
for(int msk = 1 ; msk < (1 << n) ; msk++){
for(int v = 0 ; v < n ; v++){
if(!((msk >> v) & 1)) continue;
inf[v] = 0;
for(int u = 0 ; u < v ; u++) if(((msk >> u) & 1) and g[u][v] == 1) inf[v]++;
}
if(msk == (1 << n) - 1){
for(int v = 0 ; v < n ; v++){
Add(dp[0][msk][0] , dp[v][msk ^ (1 << v)][0]);
Add(dp[0][msk][1] , Sum(Mul(inf[v] , dp[v][msk ^ (1 << v)][0]) , dp[v][msk ^ (1 << v)][1]));
}
}else{
for(int b = 0 ; b < n ; b++){
for(int v = 0 ; v < n ; v++){
if(!((msk >> v) & 1) or (v <= b and g[v][b] == 0)) continue;
Add(dp[b][msk][0] , dp[v][msk ^ (1 << v)][0]);
Add(dp[b][msk][1] , Sum(Mul(inf[v] , dp[v][msk ^ (1 << v)][0]) , dp[v][msk ^ (1 << v)][1]));
}
}
}
}
}
int main(){
ios::sync_with_stdio(0);
cin.tie(0);
cin >> n >> m;
for(int i = 0 ; i < m ; i++){
int v , u;
cin >> v >> u;
v-- , u--;
g[v][u] = 1 , g[u][v] = -1;
}
f();
cout << dp[0][(1 << n) - 1][1];
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
344 KB |
Output is correct |
2 |
Incorrect |
0 ms |
2392 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
344 KB |
Output is correct |
2 |
Incorrect |
0 ms |
2392 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
344 KB |
Output is correct |
2 |
Incorrect |
0 ms |
2392 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
344 KB |
Output is correct |
2 |
Incorrect |
0 ms |
2392 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
344 KB |
Output is correct |
2 |
Incorrect |
0 ms |
2392 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |