Submission #223102

# Submission time Handle Problem Language Result Execution time Memory
223102 2020-04-14T18:39:41 Z super_j6 Ruins 3 (JOI20_ruins3) C++14
100 / 100
252 ms 3200 KB
#include <iostream>
#include <cstdio>
#include <algorithm>
#include <string.h>
using namespace std;
#define endl '\n'
#define pi pair<int, int>
#define f first
#define s second
#define ll long long

const int mod = 1000000007;
const int maxn = 603;
int n;
bool a[2 * maxn];
int p[maxn], dp[maxn], dp2[maxn];
int c[maxn][maxn], f[maxn][maxn];

int main(){
	ios::sync_with_stdio(false);
	cin.tie(NULL);
	
	cin >> n;

	for(int i = 0; i < n; i++){
		int x;
		cin >> x;
		a[x] = 1;
	}
	
	f[0][0] = 1;
	for(int i = 0; i < n; i++)
	for(int j = i; j <= 2 * i && j < n; j++){
		(f[i + 1][j + 2] += f[i][j]) %= mod;
		(f[i + 1][j + 1] += 2 * f[i][j] % mod) %= mod;
		(f[i + 1][j] += f[i][j]) %= mod;
	}

	c[0][0] = 1;
	for(int i = 0, j = 1; i < n; i++){
		p[i] = (ll)f[i][i] * j % mod * (i + 2) % mod;
		j = (ll)j * (i + 1) % mod;
		for(int k = 0; k <= i; k++){
			(c[i + 1][k] += c[i][k]) %= mod;
			(c[i + 1][k + 1] += c[i][k]) %= mod;
		}
	}

	dp[0] = 1;
	for(int i = 2 * n, x = 0, y = 0; i > 0 && y <= x; i--){
		if(a[i]){
			memcpy(dp2 + y, dp + y, (x - y + 1) * sizeof(int));
			for(int j = y; j <= x; j++)
			for(int k = j; k <= x; k++){
				(dp[k + 1] += (ll)dp2[j] * c[x - j][k - j] % mod * p[k - j] % mod) %= mod;
			}
			x++;
		}else{
			for(int j = y; j <= x; j++) dp[j] = (ll)dp[j] * (j - y) % mod;
			y++;
		}
	}

	int ret = dp[n];
	for(int i = n, j = (mod + 1) / 2; i; i >>= 1){
		if(i & 1) ret = (ll)ret * j % mod;
		j = (ll)j * j % mod;
	}

	cout << ret << endl;

	return 0;
}
# Verdict Execution time Memory Grader output
1 Correct 4 ms 384 KB Output is correct
2 Correct 4 ms 384 KB Output is correct
3 Correct 4 ms 384 KB Output is correct
4 Correct 5 ms 384 KB Output is correct
5 Correct 5 ms 384 KB Output is correct
6 Correct 5 ms 384 KB Output is correct
7 Correct 4 ms 384 KB Output is correct
8 Correct 5 ms 384 KB Output is correct
9 Correct 5 ms 384 KB Output is correct
10 Correct 5 ms 384 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 4 ms 384 KB Output is correct
2 Correct 4 ms 384 KB Output is correct
3 Correct 4 ms 384 KB Output is correct
4 Correct 5 ms 384 KB Output is correct
5 Correct 5 ms 384 KB Output is correct
6 Correct 5 ms 384 KB Output is correct
7 Correct 4 ms 384 KB Output is correct
8 Correct 5 ms 384 KB Output is correct
9 Correct 5 ms 384 KB Output is correct
10 Correct 5 ms 384 KB Output is correct
11 Correct 5 ms 640 KB Output is correct
12 Correct 5 ms 640 KB Output is correct
13 Correct 5 ms 640 KB Output is correct
14 Correct 5 ms 640 KB Output is correct
15 Correct 8 ms 640 KB Output is correct
16 Correct 5 ms 640 KB Output is correct
17 Correct 5 ms 640 KB Output is correct
18 Correct 5 ms 640 KB Output is correct
19 Correct 5 ms 640 KB Output is correct
20 Correct 5 ms 640 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 4 ms 384 KB Output is correct
2 Correct 4 ms 384 KB Output is correct
3 Correct 4 ms 384 KB Output is correct
4 Correct 5 ms 384 KB Output is correct
5 Correct 5 ms 384 KB Output is correct
6 Correct 5 ms 384 KB Output is correct
7 Correct 4 ms 384 KB Output is correct
8 Correct 5 ms 384 KB Output is correct
9 Correct 5 ms 384 KB Output is correct
10 Correct 5 ms 384 KB Output is correct
11 Correct 5 ms 640 KB Output is correct
12 Correct 5 ms 640 KB Output is correct
13 Correct 5 ms 640 KB Output is correct
14 Correct 5 ms 640 KB Output is correct
15 Correct 8 ms 640 KB Output is correct
16 Correct 5 ms 640 KB Output is correct
17 Correct 5 ms 640 KB Output is correct
18 Correct 5 ms 640 KB Output is correct
19 Correct 5 ms 640 KB Output is correct
20 Correct 5 ms 640 KB Output is correct
21 Correct 9 ms 3200 KB Output is correct
22 Correct 8 ms 3200 KB Output is correct
23 Correct 9 ms 3200 KB Output is correct
24 Correct 13 ms 3200 KB Output is correct
25 Correct 8 ms 3200 KB Output is correct
26 Correct 8 ms 3200 KB Output is correct
27 Correct 8 ms 3200 KB Output is correct
28 Correct 8 ms 3200 KB Output is correct
29 Correct 8 ms 3200 KB Output is correct
30 Correct 252 ms 3200 KB Output is correct
31 Correct 139 ms 3200 KB Output is correct
32 Correct 174 ms 3200 KB Output is correct
33 Correct 215 ms 3200 KB Output is correct
34 Correct 121 ms 3200 KB Output is correct
35 Correct 186 ms 3200 KB Output is correct
36 Correct 220 ms 3200 KB Output is correct