#define DEBUG 0
#include <bits/stdc++.h>
using namespace std;
#if DEBUG
// basic debugging macros
int __i__,__j__;
#define printLine(l) for(__i__=0;__i__<l;__i__++){cout<<"-";}cout<<endl
#define printLine2(l,c) for(__i__=0;__i__<l;__i__++){cout<<c;}cout<<endl
#define printVar(n) cout<<#n<<": "<<n<<endl
#define printArr(a,l) cout<<#a<<": ";for(__i__=0;__i__<l;__i__++){cout<<a[__i__]<<" ";}cout<<endl
#define print2dArr(a,r,c) cout<<#a<<":\n";for(__i__=0;__i__<r;__i__++){for(__j__=0;__j__<c;__j__++){cout<<a[__i__][__j__]<<" ";}cout<<endl;}
#define print2dArr2(a,r,c,l) cout<<#a<<":\n";for(__i__=0;__i__<r;__i__++){for(__j__=0;__j__<c;__j__++){cout<<setw(l)<<setfill(' ')<<a[__i__][__j__]<<" ";}cout<<endl;}
// advanced debugging class
// debug 1,2,'A',"test";
class _Debug {
public:
template<typename T>
_Debug& operator,(T val) {
cout << val << endl;
return *this;
}
};
#define debug _Debug(),
#else
#define printLine(l)
#define printLine2(l,c)
#define printVar(n)
#define printArr(a,l)
#define print2dArr(a,r,c)
#define print2dArr2(a,r,c,l)
#define debug
#endif
// define
#define MAX_VAL 999999999
#define MAX_VAL_2 999999999999999999LL
#define EPS 1e-6
#define mp make_pair
#define pb push_back
// typedef
typedef unsigned int UI;
typedef long long int LLI;
typedef unsigned long long int ULLI;
typedef unsigned short int US;
typedef pair<int,int> pii;
typedef pair<LLI,LLI> plli;
typedef vector<int> vi;
typedef vector<LLI> vlli;
typedef vector<pii> vpii;
typedef vector<plli> vplli;
// ---------- END OF TEMPLATE ----------
#define MOD 1000000007
int rem[1200];
int C[600][600],temp[600][600],ways[600];
int dp[1201][601];
int main() {
int i;
int N,A;
scanf("%d",&N);
for (i = 0; i < N; i++) scanf("%d",&A),rem[A-1] = 1;
reverse(rem,rem+2*N);
int j,k,c = 0;
dp[0][0] = 1;
for (i = 0; i < N; i++) {
C[i][0] = 1;
for (j = 1; j <= i; j++) C[i][j] = (C[i-1][j-1]+C[i-1][j]) % MOD;
}
for (i = 0; i < N; i++) {
if (i == 0) temp[0][0] = 1;
else {
for (j = 0; j <= i; j++) {
temp[i][j] = temp[i-1][j];
if (j > 0) temp[i][j] = (temp[i][j]+(LLI) temp[i-1][j-1]*((MOD+1)/2)) % MOD;
if (j < i-1) temp[i][j] = (temp[i][j]+(LLI) temp[i-1][j+1]*((MOD+1)/2)) % MOD;
}
}
ways[i] = temp[i][0];
for (j = 1; j <= i; j++) ways[i] = ((LLI) ways[i]*j) % MOD;
}
for (i = 0; i < 2*N; i++) {
for (j = 0; j <= min(i+1,N); j++) {
if (dp[i][j] == 0) continue;
if (!rem[i]) dp[i+1][j] = (j <= c) ? 0:((LLI) dp[i][j]*(j-c)) % MOD;
else {
for (k = j; k <= min(i-c+1,N); k++) {
if (j == k) dp[i+1][k] += dp[i][j];
else {
LLI x = ((LLI) C[i-c-j][k-j-1]*ways[k-j-1]) % MOD;
x *= k-j+1,x %= MOD;
x *= (MOD+1)/2,x %= MOD;
dp[i+1][k] += (x*dp[i][j]) % MOD;
}
if (dp[i+1][k] >= MOD) dp[i+1][k] -= MOD;
}
}
}
c += !rem[i];
}
printf("%d\n",dp[2*N][N]);
return 0;
}
Compilation message
ruins3.cpp: In function 'int main()':
ruins3.cpp:65:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
65 | scanf("%d",&N);
| ~~~~~^~~~~~~~~
ruins3.cpp:66:34: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
66 | for (i = 0; i < N; i++) scanf("%d",&A),rem[A-1] = 1;
| ~~~~~^~~~~~~~~
# |
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 |
332 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 |
332 KB |
Output is correct |
8 |
Correct |
1 ms |
332 KB |
Output is correct |
9 |
Correct |
1 ms |
436 KB |
Output is correct |
10 |
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 |
332 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 |
332 KB |
Output is correct |
8 |
Correct |
1 ms |
332 KB |
Output is correct |
9 |
Correct |
1 ms |
436 KB |
Output is correct |
10 |
Correct |
1 ms |
332 KB |
Output is correct |
11 |
Correct |
1 ms |
844 KB |
Output is correct |
12 |
Correct |
1 ms |
844 KB |
Output is correct |
13 |
Correct |
1 ms |
844 KB |
Output is correct |
14 |
Correct |
1 ms |
588 KB |
Output is correct |
15 |
Correct |
1 ms |
588 KB |
Output is correct |
16 |
Correct |
1 ms |
820 KB |
Output is correct |
17 |
Correct |
1 ms |
588 KB |
Output is correct |
18 |
Correct |
2 ms |
844 KB |
Output is correct |
19 |
Correct |
1 ms |
844 KB |
Output is correct |
20 |
Correct |
1 ms |
844 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 |
332 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 |
332 KB |
Output is correct |
8 |
Correct |
1 ms |
332 KB |
Output is correct |
9 |
Correct |
1 ms |
436 KB |
Output is correct |
10 |
Correct |
1 ms |
332 KB |
Output is correct |
11 |
Correct |
1 ms |
844 KB |
Output is correct |
12 |
Correct |
1 ms |
844 KB |
Output is correct |
13 |
Correct |
1 ms |
844 KB |
Output is correct |
14 |
Correct |
1 ms |
588 KB |
Output is correct |
15 |
Correct |
1 ms |
588 KB |
Output is correct |
16 |
Correct |
1 ms |
820 KB |
Output is correct |
17 |
Correct |
1 ms |
588 KB |
Output is correct |
18 |
Correct |
2 ms |
844 KB |
Output is correct |
19 |
Correct |
1 ms |
844 KB |
Output is correct |
20 |
Correct |
1 ms |
844 KB |
Output is correct |
21 |
Correct |
10 ms |
5932 KB |
Output is correct |
22 |
Correct |
8 ms |
5836 KB |
Output is correct |
23 |
Correct |
8 ms |
5876 KB |
Output is correct |
24 |
Correct |
13 ms |
5908 KB |
Output is correct |
25 |
Correct |
5 ms |
3020 KB |
Output is correct |
26 |
Correct |
8 ms |
5800 KB |
Output is correct |
27 |
Correct |
6 ms |
3116 KB |
Output is correct |
28 |
Correct |
6 ms |
5836 KB |
Output is correct |
29 |
Correct |
6 ms |
3020 KB |
Output is correct |
30 |
Correct |
788 ms |
5900 KB |
Output is correct |
31 |
Correct |
386 ms |
5896 KB |
Output is correct |
32 |
Correct |
565 ms |
6088 KB |
Output is correct |
33 |
Correct |
701 ms |
5884 KB |
Output is correct |
34 |
Correct |
412 ms |
5828 KB |
Output is correct |
35 |
Correct |
574 ms |
5824 KB |
Output is correct |
36 |
Correct |
707 ms |
5924 KB |
Output is correct |