oj.uz

Submission #204195

# Submission time Handle Problem Language Result Execution time Memory
204195 2020-02-25T06:42:30 Z amoo_safar Skyscraper (JOI16_skyscraper) C++14
100 / 100
 121 ms 16360 KB 
#include <bits/stdc++.h>

#define pb push_back
#define F first
#define S second
#define all(x) x.begin(), x.end()
#define debug(x) cerr << #x << " : " << x << '\n'

using namespace std;

typedef long long ll;
typedef long double ld;
typedef string str;
typedef pair<ll, ll> pll;

const ll Mod = 1000000007LL;
const int N = 1e2 + 10;
const int L = 1e3 + 10;
const ll Inf = 2242545357980376863LL;
const ll Log = 30;

int n, l, a[N], ps[N];
int mul(int a, int b){
	return (1ll * a * b) % Mod;
}
int mn[N][L][2][2];
int dp[N][N][L][2][2];

int Get(int l, int r){
	return ps[max(0, r)] - ps[max(0, l)];
}

int main(){
	ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
	cin >> n >> l;
	if(n == 1) return cout << "1\n", 0;

	for(int i = 0; i < n; i++) cin >> a[i];
	sort(a, a + n);
	for(int i = 1; i <= n; i++) ps[i] = ps[i - 1] + a[i - 1];
	for(int i = 1; i <= n; i++){
		for(int j = 1; j <= i; j++){
			int p = n - i;
			mn[i][j][0][0] = 2 * Get(p - (j-1), p) + Get(p - (j+1), p - (j-1));
			mn[i][j][0][1] = 2 * Get(p - (j-1), p) + Get(p - j, p - (j-1));
			mn[i][j][1][0] = 2 * Get(p - (j-1), p) + Get(p - j, p - (j-1));
			mn[i][j][1][1] = 2 * Get(p - (j-1), p);	
		}
	}
	reverse(a, a + n);
	dp[1][1][ 2*a[0] - mn[1][1][0][0] ][0][0] = 1;
	dp[1][1][ a[0] - mn[1][1][1][0] ][1][0] = 1;
	dp[1][1][ a[0] - mn[1][1][0][1] ][0][1] = 1;
	
	int C, nC, X, P;
	for(int i = 1; i < n; i++){
		X = a[i];
		for(int j = 1; j <= i; j++){
			for(int c = 0; c <= l; c++){
				for(int b1 = 0; b1 < 2; b1++){ for(int b2 = 0; b2 < 2; b2++){
					if(!dp[i][j][c][b1][b2]) continue;
					C = c + mn[i][j][b1][b2];
					if(!b1){
						nC = C + X - mn[i + 1][j + 1][1][b2];
						if(0 <= nC && nC <= l)
							(dp[i + 1][j + 1][nC][1][b2] += dp[i][j][c][b1][b2]) %= Mod;
						
						nC = C - X - mn[i + 1][j][1][b2];
						if(0 <= nC && nC <= l)
							(dp[i + 1][j][nC][1][b2] += dp[i][j][c][b1][b2]) %= Mod;
					}
					if(!b2){
						nC = C + X - mn[i + 1][j + 1][b1][1];
						if(0 <= nC && nC <= l)
							(dp[i + 1][j + 1][nC][b1][1] += dp[i][j][c][b1][b2]) %= Mod;
						
						nC = C - X - mn[i + 1][j][b1][1];
						if(0 <= nC && nC <= l)
							(dp[i + 1][j][nC][b1][1] += dp[i][j][c][b1][b2]) %= Mod;
					}

					P = 2 * j - b1 - b2;
					nC = C - mn[i + 1][j][b1][b2];
					if(0 <= nC && nC <= l)
						(dp[i + 1][j][nC][b1][b2] += mul(P, dp[i][j][c][b1][b2]) ) %= Mod;
					
					P = j + 1 - b1 - b2;
					nC = C + 2*X - mn[i + 1][j + 1][b1][b2];
					if(0 <= nC && nC <= l)
						(dp[i + 1][j + 1][nC][b1][b2] += mul(P, dp[i][j][c][b1][b2]) ) %= Mod;

					P = j - 1;
					nC = C - 2*X - mn[i + 1][j - 1][b1][b2];
					if(0 <= nC && nC <= l)
						(dp[i + 1][j - 1][nC][b1][b2] += mul(P, dp[i][j][c][b1][b2]) ) %= Mod;
				}
				}
			}
		}
	}

	int ans = 0;
	for(int i = 0; i <= l; i++){
		ans = (ans + dp[n][1][i][1][1]) % Mod;
	}
	cout << ans << '\n';
	return 0;
}

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 376 KB Output is correct
2 Correct 5 ms 376 KB Output is correct
3 Correct 5 ms 376 KB Output is correct
4 Correct 5 ms 504 KB Output is correct
5 Correct 5 ms 632 KB Output is correct
6 Correct 5 ms 504 KB Output is correct
7 Correct 5 ms 504 KB Output is correct
8 Correct 5 ms 504 KB Output is correct
9 Correct 6 ms 632 KB Output is correct
10 Correct 5 ms 632 KB Output is correct

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 760 KB Output is correct
2 Correct 5 ms 632 KB Output is correct
3 Correct 5 ms 760 KB Output is correct
4 Correct 5 ms 632 KB Output is correct
5 Correct 5 ms 760 KB Output is correct
6 Correct 6 ms 760 KB Output is correct
7 Correct 5 ms 632 KB Output is correct
8 Correct 5 ms 760 KB Output is correct
9 Correct 6 ms 760 KB Output is correct
10 Correct 5 ms 632 KB Output is correct

Subtask #3
80.0 / 80.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 376 KB Output is correct
2 Correct 5 ms 376 KB Output is correct
3 Correct 5 ms 376 KB Output is correct
4 Correct 5 ms 504 KB Output is correct
5 Correct 5 ms 632 KB Output is correct
6 Correct 5 ms 504 KB Output is correct
7 Correct 5 ms 504 KB Output is correct
8 Correct 5 ms 504 KB Output is correct
9 Correct 6 ms 632 KB Output is correct
10 Correct 5 ms 632 KB Output is correct
11 Correct 6 ms 760 KB Output is correct
12 Correct 5 ms 632 KB Output is correct
13 Correct 5 ms 760 KB Output is correct
14 Correct 5 ms 632 KB Output is correct
15 Correct 5 ms 760 KB Output is correct
16 Correct 6 ms 760 KB Output is correct
17 Correct 5 ms 632 KB Output is correct
18 Correct 5 ms 760 KB Output is correct
19 Correct 6 ms 760 KB Output is correct
20 Correct 5 ms 632 KB Output is correct
21 Correct 6 ms 1400 KB Output is correct
22 Correct 121 ms 16360 KB Output is correct
23 Correct 85 ms 7928 KB Output is correct
24 Correct 82 ms 9720 KB Output is correct
25 Correct 80 ms 7416 KB Output is correct
26 Correct 75 ms 7160 KB Output is correct
27 Correct 38 ms 7800 KB Output is correct
28 Correct 48 ms 9336 KB Output is correct
29 Correct 87 ms 11768 KB Output is correct
30 Correct 83 ms 8072 KB Output is correct