#include <bits/stdc++.h>
using namespace std;
template<typename T>
void out(T x) { cout << x << endl; exit(0); }
#define watch(x) cout << (#x) << " is " << (x) << endl
using ll = long long;
const ll mod = 1e9 + 7;
const int maxn = 355;
int n;
ll dp[maxn][maxn];
const int N = 1010;
ll f[N];
ll C[N][N];
void add(ll &x, ll y) {
x %= mod;
y %= mod;
x += y;
x %= mod;
}
ll solve(int i, int j, bool flag=false) {
//cout<<i<<": "<<j<<endl;
if (i==n) {
if (flag) {
return i!=j;
}
return 1;
}
if (~dp[i][j]) return dp[i][j];
ll &res = dp[i][j] = 0;
// take x tasks
for (int x=0; x<=j; x++) {
if (flag) {
if (x==i) continue;
}
add(res, C[j][x]*solve(i+1,j-x,flag));
}
return res;
}
int main() {
ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
f[0]=1;
for (int i=1; i<N; i++) {
f[i]=i*f[i-1]%mod;
}
for (int i=0; i<N; i++) {
C[i][0]=C[i][i]=1;
for (int j=1; j<i; j++) {
C[i][j]=(C[i-1][j-1]+C[i-1][j])%mod;
}
}
assert(C[4][2]==6);
cin>>n;
memset(dp,-1,sizeof(dp));
ll all = solve(1, n);
memset(dp,-1,sizeof(dp));
ll none = solve(1,n,true);
ll res = all - none;
res %= mod;
res += mod;
res %= mod;
cout<<res<<endl;
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
6 ms |
8300 KB |
Output is correct |
2 |
Correct |
6 ms |
8300 KB |
Output is correct |
3 |
Correct |
6 ms |
8328 KB |
Output is correct |
4 |
Correct |
6 ms |
8320 KB |
Output is correct |
5 |
Correct |
6 ms |
8300 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
6 ms |
8300 KB |
Output is correct |
2 |
Correct |
6 ms |
8300 KB |
Output is correct |
3 |
Correct |
6 ms |
8328 KB |
Output is correct |
4 |
Correct |
6 ms |
8320 KB |
Output is correct |
5 |
Correct |
6 ms |
8300 KB |
Output is correct |
6 |
Correct |
6 ms |
8300 KB |
Output is correct |
7 |
Correct |
6 ms |
8300 KB |
Output is correct |
8 |
Correct |
6 ms |
8300 KB |
Output is correct |
9 |
Correct |
6 ms |
8300 KB |
Output is correct |
10 |
Correct |
6 ms |
8300 KB |
Output is correct |
11 |
Correct |
6 ms |
8300 KB |
Output is correct |
12 |
Correct |
6 ms |
8300 KB |
Output is correct |
13 |
Correct |
6 ms |
8300 KB |
Output is correct |
14 |
Correct |
6 ms |
8320 KB |
Output is correct |
15 |
Correct |
6 ms |
8300 KB |
Output is correct |
16 |
Correct |
6 ms |
8300 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
6 ms |
8300 KB |
Output is correct |
2 |
Correct |
6 ms |
8300 KB |
Output is correct |
3 |
Correct |
6 ms |
8328 KB |
Output is correct |
4 |
Correct |
6 ms |
8320 KB |
Output is correct |
5 |
Correct |
6 ms |
8300 KB |
Output is correct |
6 |
Correct |
6 ms |
8300 KB |
Output is correct |
7 |
Correct |
6 ms |
8300 KB |
Output is correct |
8 |
Correct |
6 ms |
8300 KB |
Output is correct |
9 |
Correct |
6 ms |
8300 KB |
Output is correct |
10 |
Correct |
6 ms |
8300 KB |
Output is correct |
11 |
Correct |
6 ms |
8300 KB |
Output is correct |
12 |
Correct |
6 ms |
8300 KB |
Output is correct |
13 |
Correct |
6 ms |
8300 KB |
Output is correct |
14 |
Correct |
6 ms |
8320 KB |
Output is correct |
15 |
Correct |
6 ms |
8300 KB |
Output is correct |
16 |
Correct |
6 ms |
8300 KB |
Output is correct |
17 |
Correct |
266 ms |
8428 KB |
Output is correct |
18 |
Correct |
7 ms |
8300 KB |
Output is correct |
19 |
Correct |
60 ms |
8416 KB |
Output is correct |
20 |
Correct |
6 ms |
8300 KB |
Output is correct |
21 |
Correct |
333 ms |
8556 KB |
Output is correct |
22 |
Correct |
44 ms |
8300 KB |
Output is correct |
23 |
Correct |
9 ms |
8300 KB |
Output is correct |
24 |
Correct |
81 ms |
8300 KB |
Output is correct |
25 |
Correct |
50 ms |
8300 KB |
Output is correct |
26 |
Correct |
99 ms |
8428 KB |
Output is correct |
27 |
Correct |
467 ms |
8436 KB |
Output is correct |
28 |
Correct |
473 ms |
8556 KB |
Output is correct |
29 |
Correct |
472 ms |
8556 KB |
Output is correct |
30 |
Correct |
477 ms |
8436 KB |
Output is correct |
31 |
Correct |
483 ms |
8428 KB |
Output is correct |
32 |
Correct |
510 ms |
8428 KB |
Output is correct |
33 |
Correct |
495 ms |
8436 KB |
Output is correct |
34 |
Correct |
497 ms |
8556 KB |
Output is correct |
35 |
Correct |
502 ms |
8436 KB |
Output is correct |
36 |
Correct |
503 ms |
8436 KB |
Output is correct |
37 |
Correct |
505 ms |
8556 KB |
Output is correct |