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답안 #282929

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
282929 2020-08-25T07:27:19 Z AMO5 Zapina (COCI20_zapina) C++17
110 / 110
 180 ms 3832 KB 
#include <bits/stdc++.h>

using namespace std;

#define fi first
#define se second
#define eb emplace_back
#define mt make_tuple
#define all(x) (x).begin(), (x).end()  
#define sz(x) int(x.size()) 
#define MOD 1000000007

typedef long long ll;
typedef pair <int, int> ii;
typedef pair <ll, ll> pll;
typedef vector<int> vi;
typedef vector<ll> vll;
typedef long double ld;

const ll INF=63;
const int mxn=400;
bool DEBUG=0;

ll choose[mxn][mxn],dp[mxn][mxn][2];

void jia(ll &a, ll b){
	a=1ll*(a+b)%MOD;
}

ll mul(ll a, ll b){
	return 1ll*a*b%MOD;
}

ll modpow(ll a, ll b){
	ll res = 1ll;
	while(b){
		if(b&1)jia(res,a);
		mul(a,a);
		b/=2;
	}
	return res%MOD;
}

void init(){
	for(int i=0; i<mxn; i++){
		choose[i][0]=1ll;
		for(int j=1; j<=i; j++){
			choose[i][j]=(choose[i-1][j-1]+choose[i-1][j])%MOD;
		}
	}
}

int n;

int main()
{
    ios_base::sync_with_stdio(0); cin.tie(0);
    //freopen("input.txt","r",stdin); freopen("output.txt","w",stdout);
    init();
    cin>>n;
    dp[1][0][0]=dp[1][1][1]=1;
    for(int i=2; i<=n; i++)
		dp[1][i][0]=1;
    for(int i=2; i<=n; i++){
		for(int j=0; j<=n; j++){
			for(int k=0; k<=j; k++){
				if(k==i){
					jia(dp[i][j][1],mul(dp[i-1][j-k][0],choose[j][k]));
					jia(dp[i][j][1],mul(dp[i-1][j-k][1],choose[j][k]));
				}else{
					jia(dp[i][j][0],mul(dp[i-1][j-k][0],choose[j][k]));
					jia(dp[i][j][1],mul(dp[i-1][j-k][1],choose[j][k]));
				}
			}
		}
	}
	cout<<dp[n][n][1];
}
	
// READ & UNDERSTAND
// ll, int overflow, array bounds, memset(0)
// special cases (n=1?), n+1 (1-index)
// do smth instead of nothing & stay organized
// WRITE STUFF DOWN

Subtask #1
22.0 / 22.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 1536 KB Output is correct
2 Correct 1 ms 1664 KB Output is correct
3 Correct 1 ms 1536 KB Output is correct
4 Correct 1 ms 1664 KB Output is correct
5 Correct 2 ms 1664 KB Output is correct

Subtask #2
33.0 / 33.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 1536 KB Output is correct
2 Correct 1 ms 1664 KB Output is correct
3 Correct 1 ms 1536 KB Output is correct
4 Correct 1 ms 1664 KB Output is correct
5 Correct 2 ms 1664 KB Output is correct
6 Correct 2 ms 1664 KB Output is correct
7 Correct 1 ms 1664 KB Output is correct
8 Correct 2 ms 1664 KB Output is correct
9 Correct 1 ms 1664 KB Output is correct
10 Correct 1 ms 1664 KB Output is correct
11 Correct 1 ms 1664 KB Output is correct
12 Correct 2 ms 1664 KB Output is correct
13 Correct 1 ms 1664 KB Output is correct
14 Correct 2 ms 1664 KB Output is correct
15 Correct 1 ms 1664 KB Output is correct
16 Correct 1 ms 1664 KB Output is correct

Subtask #3
55.0 / 55.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 1536 KB Output is correct
2 Correct 1 ms 1664 KB Output is correct
3 Correct 1 ms 1536 KB Output is correct
4 Correct 1 ms 1664 KB Output is correct
5 Correct 2 ms 1664 KB Output is correct
6 Correct 2 ms 1664 KB Output is correct
7 Correct 1 ms 1664 KB Output is correct
8 Correct 2 ms 1664 KB Output is correct
9 Correct 1 ms 1664 KB Output is correct
10 Correct 1 ms 1664 KB Output is correct
11 Correct 1 ms 1664 KB Output is correct
12 Correct 2 ms 1664 KB Output is correct
13 Correct 1 ms 1664 KB Output is correct
14 Correct 2 ms 1664 KB Output is correct
15 Correct 1 ms 1664 KB Output is correct
16 Correct 1 ms 1664 KB Output is correct
17 Correct 99 ms 3320 KB Output is correct
18 Correct 4 ms 1792 KB Output is correct
19 Correct 23 ms 2560 KB Output is correct
20 Correct 2 ms 1664 KB Output is correct
21 Correct 122 ms 3448 KB Output is correct
22 Correct 14 ms 2432 KB Output is correct
23 Correct 3 ms 1920 KB Output is correct
24 Correct 31 ms 2680 KB Output is correct
25 Correct 22 ms 2528 KB Output is correct
26 Correct 34 ms 2808 KB Output is correct
27 Correct 171 ms 3704 KB Output is correct
28 Correct 176 ms 3696 KB Output is correct
29 Correct 173 ms 3772 KB Output is correct
30 Correct 176 ms 3768 KB Output is correct
31 Correct 178 ms 3704 KB Output is correct
32 Correct 179 ms 3704 KB Output is correct
33 Correct 179 ms 3704 KB Output is correct
34 Correct 178 ms 3704 KB Output is correct
35 Correct 180 ms 3704 KB Output is correct
36 Correct 176 ms 3808 KB Output is correct
37 Correct 175 ms 3832 KB Output is correct