#include <bits/stdc++.h>
using namespace std;
#define fi first
#define se second
#define mp make_pair
#define pb push_back
#define pf push_front
#define iter(v, i) for (__typeof__((v).begin()) i = (v).begin(); i != (v).end(); i++)
#define fast_io_without_cstdio ios_base::sync_with_stdio(false), cin.tie(NULL)
#define all(v) (v).begin(), (v).end()
#define rep(i, s, e) for (int i = s; i < e; i++)
// START for segment tree
#define params int p, int L, int R
#define housekeep int mid = (L + R) >> 1, left = p << 1, right = left | 1
// END
#ifdef __linux__
#define gc getchar_unlocked
#define pc putchar_unlocked
#else
#define gc getchar
#define pc putchar
#endif
#if __cplusplus <= 199711L
template<class BidirIt>
BidirIt prev(BidirIt it, typename iterator_traits<BidirIt>::difference_type n = 1) {
advance(it, -n);
return it;
}
template<class ForwardIt>
ForwardIt next(ForwardIt it, typename iterator_traits<ForwardIt>::difference_type n = 1) {
advance(it, n);
return it;
}
#endif
typedef long long ll;
typedef pair<int, int> ii;
typedef vector<int> vi;
typedef vector<ii> vii;
typedef long double ldouble;
const double EPS = 1e-9;
const double PI = 3.141592653589793238462;
template<typename T>
inline T sq(T a) { return a * a; }
//#ifdef LOCAL_MACHINE
//#endif
const int MOD = 1e9 + 7;
const int MAXN = 3005;
inline int mul_mod(int a, int b) {
return a * 1LL * b % MOD;
}
inline void add_mod(int &a, int b) {
a += b;
if (a >= MOD) a -= MOD;
}
inline void sub_mod(int &a, int b) {
a -= b;
if (a < 0) a += MOD;
}
int dp[MAXN][MAXN];
int main() {
//freopen("", "r", stdin);
//freopen("", "w", stdout);
int n, m;
scanf("%d %d", &n, &m);
for (int i = 0; i <= n; i++)
dp[i][0] = 1;
for (int j = 0; j <= m; j++)
dp[0][j] = 1;
for (int i = 1; i <= n; i++) {
for (int j = 1; j <= m; j++) {
dp[i][j] = mul_mod(dp[i - 1][j - 1], 4 * j);
add_mod(dp[i][j], dp[i - 1][j]);
if (j >= 2)
add_mod(dp[i][j], mul_mod(j * (j - 1) / 2, dp[i - 1][j - 2]));
if (i >= 2)
add_mod(dp[i][j], mul_mod(j * (i - 1), dp[i - 2][j - 1]));
}
}
sub_mod(dp[n][m], 1);
printf("%d\n", dp[n][m]);
return 0;
}
Compilation message
tents.cpp: In function 'int main()':
tents.cpp:80:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d %d", &n, &m);
~~~~~^~~~~~~~~~~~~~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
376 KB |
Output is correct |
2 |
Correct |
2 ms |
496 KB |
Output is correct |
3 |
Correct |
2 ms |
552 KB |
Output is correct |
4 |
Correct |
2 ms |
1368 KB |
Output is correct |
5 |
Correct |
2 ms |
1368 KB |
Output is correct |
6 |
Correct |
3 ms |
1596 KB |
Output is correct |
7 |
Correct |
2 ms |
1596 KB |
Output is correct |
8 |
Correct |
3 ms |
1620 KB |
Output is correct |
9 |
Correct |
2 ms |
1620 KB |
Output is correct |
10 |
Correct |
3 ms |
2068 KB |
Output is correct |
11 |
Correct |
2 ms |
2068 KB |
Output is correct |
12 |
Correct |
4 ms |
2204 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
376 KB |
Output is correct |
2 |
Correct |
2 ms |
496 KB |
Output is correct |
3 |
Correct |
2 ms |
552 KB |
Output is correct |
4 |
Correct |
2 ms |
1368 KB |
Output is correct |
5 |
Correct |
2 ms |
1368 KB |
Output is correct |
6 |
Correct |
3 ms |
1596 KB |
Output is correct |
7 |
Correct |
2 ms |
1596 KB |
Output is correct |
8 |
Correct |
3 ms |
1620 KB |
Output is correct |
9 |
Correct |
2 ms |
1620 KB |
Output is correct |
10 |
Correct |
3 ms |
2068 KB |
Output is correct |
11 |
Correct |
2 ms |
2068 KB |
Output is correct |
12 |
Correct |
4 ms |
2204 KB |
Output is correct |
13 |
Correct |
2 ms |
2204 KB |
Output is correct |
14 |
Correct |
8 ms |
10020 KB |
Output is correct |
15 |
Correct |
83 ms |
33360 KB |
Output is correct |
16 |
Correct |
7 ms |
33360 KB |
Output is correct |
17 |
Correct |
20 ms |
33360 KB |
Output is correct |
18 |
Correct |
24 ms |
33360 KB |
Output is correct |
19 |
Correct |
89 ms |
34968 KB |
Output is correct |
20 |
Correct |
73 ms |
34968 KB |
Output is correct |
21 |
Correct |
48 ms |
34968 KB |
Output is correct |
22 |
Correct |
50 ms |
34968 KB |
Output is correct |
23 |
Correct |
38 ms |
34968 KB |
Output is correct |
24 |
Correct |
112 ms |
36028 KB |
Output is correct |
25 |
Correct |
88 ms |
36028 KB |
Output is correct |
26 |
Correct |
101 ms |
36028 KB |
Output is correct |
27 |
Correct |
111 ms |
36028 KB |
Output is correct |