#include<bits/stdc++.h>
#define endl '\n'
using namespace std;
const long long MAXN = 25, MAXMASK = 2e6+10;
void speed()
{
ios_base::sync_with_stdio(false);
cin.tie(NULL);
cout.tie(NULL);
}
long long n, a[MAXN], cnt2[MAXN], cnt3[MAXN];
long long cnt_bin_2(long long x)
{
long long cnt = 0;
while(x)
{
if(x % 2 == 0)cnt ++;
x /= 2;
}
return cnt;
}
long long cnt_bin_3(long long x)
{
long long cnt = 0;
while(x)
{
if(x % 3 == 0)cnt ++;
x /= 3;
}
return cnt;
}
long long dp[MAXMASK][MAXN];
map < int, int > mp;
void read()
{
cin >> n;
for (long long i = 1; i <= n; ++ i)
{
cin >> a[i];
cnt2[i] = cnt_bin_2(a[i]);
cnt3[i] = cnt_bin_3(a[i]);
}
}
void solve()
{
for (long long i = 1; i <= n; ++ i)
dp[(1 << (i-1))][i] = 1;
for (long long mask = 1; mask < (1 << n); ++ mask)
{
for (long long last = 1; last <= n; ++ last)
{
if(((1 << (last-1)) & mask) == 0)continue;
for (long long j = 1; j <= n; ++ j)
{
if(((1 << (j-1)) & mask) != 0)continue;
if(cnt2[j] != cnt2[last] && cnt2[j] != cnt3[last] && cnt3[j] != cnt2[last] && cnt3[j] != cnt3[last])continue;
long long newmask = (mask | (1 << (j-1)));
dp[newmask][j] += dp[mask][last];
}
}
}
long long ans = 0;
for (long long i = 1; i <= n; ++ i)
{
ans += dp[(1 << n)-1][i];
}
sort(a+1, a+n+1);
for (int i = 1; i <= n; ++ i)
{
mp[a[i]] ++;
if(a[i+1] != a[i])
{
int del = mp[a[i]];
for (int j = del; j >= 1; -- j)
ans /= j;
}
}
cout << ans << endl;
}
int main()
{
speed();
read();
solve();
return 0;
}
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
0 ms |
344 KB |
Output is correct |
| 2 |
Correct |
0 ms |
348 KB |
Output is correct |
| 3 |
Incorrect |
1 ms |
348 KB |
Output isn't correct |
| 4 |
Halted |
0 ms |
0 KB |
- |
