#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int maxn = 5e5 + 100;
const int mod = (int)1e9+7;
int n;
int a[maxn];
int g[22][22];
ll dp[1<<20][20];
int ter(int x) {
int cnt = 0;
while(x > 0) {
if(x % 3 == 1) cnt++;
x /= 3;
}
return cnt;
}
ll rec(int mask, int last) {
if(__builtin_popcount(mask) == n) {
return 1;
}
if(dp[mask][last] != -1) return dp[mask][last];
dp[mask][last] = 0;
for(int i = 0; i < n; i++) {
if(g[last][i] && !(mask & (1<<i))) {
dp[mask][last] += rec(mask|1<<i, i);
}
}
return dp[mask][last];
}
int main() {
ios_base::sync_with_stdio(false);
cin >> n;
for(int i = 0; i < n; i++) {
cin >> a[i];
}
for(int i = 0; i < n; i++) {
for(int j = 0; j < n; j++) {
if(__builtin_popcount(a[i]) == __builtin_popcount(a[j])) {
g[i][j] = 1;
} else {
if(ter(a[i]) == ter(a[j])) {
g[i][j] = 1;
}
}
}
}
memset(dp, -1, sizeof dp);
ll ans = 0;
for(int i = 0; i < n; i++) {
ans += rec(1<<i, i);
}
cout << ans << "\n";
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
60 ms |
164428 KB |
Output is correct |
2 |
Correct |
62 ms |
164436 KB |
Output is correct |
3 |
Correct |
73 ms |
164352 KB |
Output is correct |
4 |
Correct |
63 ms |
164392 KB |
Output is correct |
5 |
Correct |
59 ms |
164416 KB |
Output is correct |
6 |
Correct |
60 ms |
164428 KB |
Output is correct |
7 |
Correct |
59 ms |
164376 KB |
Output is correct |
8 |
Correct |
63 ms |
164428 KB |
Output is correct |
9 |
Correct |
62 ms |
164468 KB |
Output is correct |
10 |
Correct |
65 ms |
164412 KB |
Output is correct |
11 |
Correct |
82 ms |
164472 KB |
Output is correct |
12 |
Correct |
75 ms |
164452 KB |
Output is correct |
13 |
Correct |
147 ms |
164468 KB |
Output is correct |
14 |
Correct |
427 ms |
164416 KB |
Output is correct |
15 |
Correct |
451 ms |
164464 KB |
Output is correct |
16 |
Correct |
298 ms |
164556 KB |
Output is correct |
17 |
Correct |
397 ms |
164520 KB |
Output is correct |
18 |
Correct |
247 ms |
164468 KB |
Output is correct |
19 |
Correct |
2293 ms |
164464 KB |
Output is correct |
20 |
Correct |
2531 ms |
164468 KB |
Output is correct |