#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef double lf;
typedef pair<ll,ll> ii;
#define REP(i,n) for(int i=0;i<n;i++)
#define REP1(i,n) for(ll i=1;i<=n;i++)
#define RST(i,n) memset(i,n,sizeof i)
#define SZ(a) (int)a.size()
#define ALL(a) a.begin(),a.end()
#define X first
#define Y second
#define mkp make_pair
#define pb push_back
#define eb emplace_back
#define pob pop_back
#ifdef cold66
#define debug(...) do{\
fprintf(stderr,"%s - %d (%s) = ",__PRETTY_FUNCTION__,__LINE__,#__VA_ARGS__);\
_do(__VA_ARGS__);\
}while(0)
template<typename T>void _do(T &&_x){cerr<<_x<<endl;}
template<typename T,typename ...S> void _do(T &&_x,S &&..._t){cerr<<_x<<", ";_do(_t...);}
template<typename _a,typename _b> ostream& operator << (ostream &_s,const pair<_a,_b> &_p){return _s<<"("<<_p.X<<","<<_p.Y<<")";}
template<typename It> ostream& _OUTC(ostream &_s,It _ita,It _itb)
{
_s<<"{";
for(It _it=_ita;_it!=_itb;_it++)
{
_s<<(_it==_ita?"":",")<<*_it;
}
_s<<"}";
return _s;
}
template<typename _a> ostream &operator << (ostream &_s,vector<_a> &_c){return _OUTC(_s,ALL(_c));}
template<typename _a> ostream &operator << (ostream &_s,set<_a> &_c){return _OUTC(_s,ALL(_c));}
template<typename _a,typename _b> ostream &operator << (ostream &_s,map<_a,_b> &_c){return _OUTC(_s,ALL(_c));}
template<typename _t> void pary(_t _a,_t _b){_OUTC(cerr,_a,_b);cerr<<endl;}
#define IOS()
#else
#define debug(...)
#define pary(...)
#define endl '\n'
#define IOS() ios_base::sync_with_stdio(0);cin.tie(0);
#endif // cold66
//}
template<class T> inline bool chkmax(T &a, const T &b) { return b > a ? a = b, true : false; }
template<class T> inline bool chkmin(T &a, const T &b) { return b < a ? a = b, true : false; }
template<class T> using MaxHeap = priority_queue<T>;
template<class T> using MinHeap = priority_queue<T, vector<T>, greater<T>>;
const ll MAXn=3e3+5,MAXlg=__lg(MAXn)+2;
const ll MOD=1000000007;
const ll INF=0x3f3f3f3f;
ll dp[MAXn][MAXn];
ll mul(ll a,ll b){
return a*b%MOD;
}
ll add(ll a,ll b){
ll ret = a + b;
if (ret >= MOD) ret -= MOD;
return ret;
}
ll sub(ll a,ll b){
ll ret = a-b;
if (ret < 0) ret += MOD;
return ret;
}
int main(){
IOS();
int n,m;
cin >> n >> m;
REP (i,n+1) {
REP (j,m+1) {
if (!i || !j) dp[i][j] = 1;
else {
dp[i][j] = dp[i][j-1];
dp[i][j] = add(dp[i][j],mul(4,mul(i,dp[i-1][j-1])));
if (i >= 2) dp[i][j] = add(dp[i][j],mul((i-1)*i/2,dp[i-2][j-1]));
if (j >= 2) dp[i][j] = add(dp[i][j],mul(i*(j-1),dp[i-1][j-2]));
}
debug(i,j,dp[i][j]);
}
}
dp[n][m] = sub(dp[n][m],1);
cout << dp[n][m] << endl;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
5 ms |
376 KB |
Output is correct |
2 |
Correct |
5 ms |
376 KB |
Output is correct |
3 |
Correct |
5 ms |
504 KB |
Output is correct |
4 |
Correct |
5 ms |
1144 KB |
Output is correct |
5 |
Correct |
5 ms |
764 KB |
Output is correct |
6 |
Correct |
5 ms |
1400 KB |
Output is correct |
7 |
Correct |
5 ms |
888 KB |
Output is correct |
8 |
Correct |
5 ms |
1532 KB |
Output is correct |
9 |
Correct |
5 ms |
888 KB |
Output is correct |
10 |
Correct |
6 ms |
1784 KB |
Output is correct |
11 |
Correct |
5 ms |
376 KB |
Output is correct |
12 |
Correct |
7 ms |
2296 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
5 ms |
376 KB |
Output is correct |
2 |
Correct |
5 ms |
376 KB |
Output is correct |
3 |
Correct |
5 ms |
504 KB |
Output is correct |
4 |
Correct |
5 ms |
1144 KB |
Output is correct |
5 |
Correct |
5 ms |
764 KB |
Output is correct |
6 |
Correct |
5 ms |
1400 KB |
Output is correct |
7 |
Correct |
5 ms |
888 KB |
Output is correct |
8 |
Correct |
5 ms |
1532 KB |
Output is correct |
9 |
Correct |
5 ms |
888 KB |
Output is correct |
10 |
Correct |
6 ms |
1784 KB |
Output is correct |
11 |
Correct |
5 ms |
376 KB |
Output is correct |
12 |
Correct |
7 ms |
2296 KB |
Output is correct |
13 |
Correct |
5 ms |
376 KB |
Output is correct |
14 |
Correct |
9 ms |
9724 KB |
Output is correct |
15 |
Correct |
98 ms |
55288 KB |
Output is correct |
16 |
Correct |
11 ms |
4216 KB |
Output is correct |
17 |
Correct |
25 ms |
12920 KB |
Output is correct |
18 |
Correct |
31 ms |
17144 KB |
Output is correct |
19 |
Correct |
111 ms |
62972 KB |
Output is correct |
20 |
Correct |
91 ms |
50936 KB |
Output is correct |
21 |
Correct |
63 ms |
33912 KB |
Output is correct |
22 |
Correct |
62 ms |
35448 KB |
Output is correct |
23 |
Correct |
40 ms |
27128 KB |
Output is correct |
24 |
Correct |
158 ms |
70904 KB |
Output is correct |
25 |
Correct |
116 ms |
61304 KB |
Output is correct |
26 |
Correct |
127 ms |
66680 KB |
Output is correct |
27 |
Correct |
140 ms |
68984 KB |
Output is correct |