#include <bits/stdc++.h>
using namespace std;
const int maxn = 20;
const int maxMask = (1 << maxn);
int n;
int a[maxn + 5];
bool areNeighbours[maxn + 5][maxn + 5];
int dp[maxMask + 5][maxn + 5];
bool bl[maxMask + 5][maxn + 5];
int cnt2(int x)
{
int res = 0;
while (x != 0)
{
if (x % 2 == 1)
{
++res;
}
x /= 2;
}
return res;
}
int cnt3(int x)
{
int res = 0;
while (x != 0)
{
if (x % 3 == 1)
{
++res;
}
x /= 3;
}
return res;
}
bool check(int x, int y)
{
int x2 = cnt2(x);
int x3 = cnt3(x);
int y2 = cnt2(y);
int y3 = cnt3(y);
return x2 == y2 || x2 == y3 || x3== y2 || x3 == y3;
}
int f(int mask, int last)
{
if (mask == (1 << n) - 1)
{
return 1;
}
if (bl[mask][last] == true)
{
return dp[mask][last];
}
bl[mask][last] = true;
int result = 0;
for (int i = 0; i < n; ++i)
{
if ((mask & (1 << i)) == 0 && areNeighbours[i][last] == true)
{
result += f((mask | (1 << i)), i);
}
}
return dp[mask][last] = result;
}
void fastIO()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
}
int main()
{
fastIO();
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 (i != j && check(a[i], a[j]) == true)
{
areNeighbours[i][j] = true;
}
}
}
int ans = 0;
for (int i = 0; i < n; ++i)
{
ans += f((1 << i), i);
}
cout << ans << endl;
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
2392 KB |
Output is correct |
2 |
Incorrect |
1 ms |
2396 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |