#include <bits/stdc++.h>
using namespace std;
#define nl "\n"
#define nf endl
#define ll long long
#define pb push_back
#define _ << ' ' <<
#define INF (ll)1e18
#define mod 1000000007
#define maxn 360
ll i, i1, j, k, k1, t, n, m, res, flag[10], a, b;
ll fc[maxn], nv[maxn], dp[maxn][maxn];
ll fxp(ll b, ll e) {
ll r = 1, k = b;
while (e != 0) {
if (e % 2) r = (r * k) % mod;
k = (k * k) % mod; e /= 2;
}
return r;
}
ll inv(ll x) {
return fxp(x, mod - 2);
}
ll bnm(ll a, ll b) {
if (a < b || b < 0) return 0;
ll r = (fc[a] * nv[b]) % mod;
r = (r * nv[a - b]) % mod;
return r;
}
int main() {
ios::sync_with_stdio(0);
cin.tie(0);
#if !ONLINE_JUDGE && !EVAL
ifstream cin("input.txt");
ofstream cout("output.txt");
#endif
fc[0] = 1; nv[0] = 1;
for (i = 1; i < maxn; i++) {
fc[i] = (i * fc[i - 1]) % mod; nv[i] = inv(fc[i]);
}
cin >> n;
dp[0][0] = 1;
for (i = 1; i <= n; i++) {
for (j = 0; j <= n; j++) {
dp[i][j] = 0;
for (k = 0; k <= j; k++) {
dp[i][j] = (dp[i][j] + dp[i - 1][k] * bnm(n - k, n - j)) % mod;
}
}
}
res = dp[n][n];
dp[0][0] = 1;
for (i = 1; i <= n; i++) {
for (j = 0; j <= n; j++) {
dp[i][j] = 0;
for (k = 0; k <= j; k++) {
if (j - k == i) continue;
dp[i][j] = (dp[i][j] + dp[i - 1][k] * bnm(n - k, n - j)) % mod;
}
}
}
res = (res - dp[n][n] + mod) % mod;
cout << res << nl;
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
332 KB |
Output is correct |
2 |
Correct |
1 ms |
332 KB |
Output is correct |
3 |
Correct |
1 ms |
332 KB |
Output is correct |
4 |
Correct |
1 ms |
328 KB |
Output is correct |
5 |
Correct |
1 ms |
332 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
332 KB |
Output is correct |
2 |
Correct |
1 ms |
332 KB |
Output is correct |
3 |
Correct |
1 ms |
332 KB |
Output is correct |
4 |
Correct |
1 ms |
328 KB |
Output is correct |
5 |
Correct |
1 ms |
332 KB |
Output is correct |
6 |
Correct |
1 ms |
332 KB |
Output is correct |
7 |
Correct |
1 ms |
328 KB |
Output is correct |
8 |
Correct |
1 ms |
332 KB |
Output is correct |
9 |
Correct |
1 ms |
332 KB |
Output is correct |
10 |
Correct |
1 ms |
332 KB |
Output is correct |
11 |
Correct |
1 ms |
332 KB |
Output is correct |
12 |
Correct |
1 ms |
332 KB |
Output is correct |
13 |
Correct |
1 ms |
332 KB |
Output is correct |
14 |
Correct |
1 ms |
332 KB |
Output is correct |
15 |
Correct |
1 ms |
332 KB |
Output is correct |
16 |
Correct |
1 ms |
332 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
332 KB |
Output is correct |
2 |
Correct |
1 ms |
332 KB |
Output is correct |
3 |
Correct |
1 ms |
332 KB |
Output is correct |
4 |
Correct |
1 ms |
328 KB |
Output is correct |
5 |
Correct |
1 ms |
332 KB |
Output is correct |
6 |
Correct |
1 ms |
332 KB |
Output is correct |
7 |
Correct |
1 ms |
328 KB |
Output is correct |
8 |
Correct |
1 ms |
332 KB |
Output is correct |
9 |
Correct |
1 ms |
332 KB |
Output is correct |
10 |
Correct |
1 ms |
332 KB |
Output is correct |
11 |
Correct |
1 ms |
332 KB |
Output is correct |
12 |
Correct |
1 ms |
332 KB |
Output is correct |
13 |
Correct |
1 ms |
332 KB |
Output is correct |
14 |
Correct |
1 ms |
332 KB |
Output is correct |
15 |
Correct |
1 ms |
332 KB |
Output is correct |
16 |
Correct |
1 ms |
332 KB |
Output is correct |
17 |
Correct |
156 ms |
1092 KB |
Output is correct |
18 |
Correct |
2 ms |
460 KB |
Output is correct |
19 |
Correct |
34 ms |
716 KB |
Output is correct |
20 |
Correct |
1 ms |
332 KB |
Output is correct |
21 |
Correct |
213 ms |
1136 KB |
Output is correct |
22 |
Correct |
23 ms |
716 KB |
Output is correct |
23 |
Correct |
2 ms |
460 KB |
Output is correct |
24 |
Correct |
44 ms |
808 KB |
Output is correct |
25 |
Correct |
30 ms |
756 KB |
Output is correct |
26 |
Correct |
60 ms |
836 KB |
Output is correct |
27 |
Correct |
296 ms |
1220 KB |
Output is correct |
28 |
Correct |
312 ms |
1268 KB |
Output is correct |
29 |
Correct |
302 ms |
1268 KB |
Output is correct |
30 |
Correct |
310 ms |
1276 KB |
Output is correct |
31 |
Correct |
306 ms |
1348 KB |
Output is correct |
32 |
Correct |
305 ms |
1276 KB |
Output is correct |
33 |
Correct |
312 ms |
1224 KB |
Output is correct |
34 |
Correct |
311 ms |
1200 KB |
Output is correct |
35 |
Correct |
334 ms |
1260 KB |
Output is correct |
36 |
Correct |
325 ms |
1348 KB |
Output is correct |
37 |
Correct |
317 ms |
1292 KB |
Output is correct |