#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int N = 2007;
const int MOD = 1e9 + 7;
int n, k, numWord, c[N];
int nCk[N][N], dp[N][N];
int main(){
ios_base::sync_with_stdio(0);
cin.tie(0);
cin >> n >> k;
map<string, int> cnt;
for(int i = 1; i <= n; i++){
string s;
cin >> s;
sort(s.begin(), s.end());
cnt[s]++;
}
for(auto p : cnt)
c[++numWord] = p.second;
for(int i = 0; i <= n; i++){
nCk[i][0] = 1;
for(int j = 1; j <= i; j++)
nCk[i][j] = (nCk[i - 1][j] + nCk[i - 1][j - 1]) % MOD;
}
dp[0][0] = 1;
for(int i = 0; i < numWord; i++)
for(int j = 0; j <= k; j++)
for(int x = 0; x <= c[i + 1]; x++){
int nxtJ = j + x * (x - 1) / 2;
if (nxtJ <= k)
dp[i + 1][nxtJ] = (dp[i + 1][nxtJ] + (ll) dp[i][j] * nCk[c[i + 1]][x] % MOD) % MOD;
}
cout << dp[numWord][k];
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
364 KB |
Output is correct |
2 |
Correct |
1 ms |
364 KB |
Output is correct |
3 |
Correct |
2 ms |
492 KB |
Output is correct |
4 |
Correct |
1 ms |
364 KB |
Output is correct |
5 |
Correct |
1 ms |
492 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
6 ms |
8556 KB |
Output is correct |
2 |
Correct |
9 ms |
11628 KB |
Output is correct |
3 |
Correct |
10 ms |
12396 KB |
Output is correct |
4 |
Correct |
12 ms |
15468 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
364 KB |
Output is correct |
2 |
Correct |
1 ms |
364 KB |
Output is correct |
3 |
Correct |
2 ms |
492 KB |
Output is correct |
4 |
Correct |
1 ms |
364 KB |
Output is correct |
5 |
Correct |
1 ms |
492 KB |
Output is correct |
6 |
Correct |
6 ms |
8556 KB |
Output is correct |
7 |
Correct |
9 ms |
11628 KB |
Output is correct |
8 |
Correct |
10 ms |
12396 KB |
Output is correct |
9 |
Correct |
12 ms |
15468 KB |
Output is correct |
10 |
Correct |
5 ms |
4972 KB |
Output is correct |
11 |
Correct |
3 ms |
3564 KB |
Output is correct |
12 |
Correct |
5 ms |
6636 KB |
Output is correct |
13 |
Correct |
6 ms |
6508 KB |
Output is correct |
14 |
Correct |
10 ms |
11136 KB |
Output is correct |
15 |
Correct |
8 ms |
10348 KB |
Output is correct |
16 |
Correct |
19 ms |
19436 KB |
Output is correct |
17 |
Correct |
16 ms |
14444 KB |
Output is correct |
18 |
Correct |
13 ms |
15212 KB |
Output is correct |