Submission #448079

#	Time	Username	Problem	Language	Result	Execution time	Memory
448079		AmShZ	Skyscraper (JOI16_skyscraper)	C++11	100 / 100	252 ms	82008 KiB

skyscraper

//khodaya khodet komak kon
# include <bits/stdc++.h>

using namespace std;

typedef long long                                        ll;
typedef long double                                      ld;
typedef pair <int, int>                                  pii;
typedef pair <pii, int>                                  ppi;
typedef pair <int, pii>                                  pip;
typedef pair <pii, pii>                                  ppp;
typedef pair <ll, ll>                                    pll;

# define A                                               first
# define B                                               second
# define endl                                            '\n'
# define sep                                             ' '
# define all(x)                                          x.begin(), x.end()
# define kill(x)                                         return cout << x << endl, 0
# define SZ(x)                                           int(x.size())
# define lc                                              id << 1
# define rc                                              id << 1 | 1
# define fast_io                                         ios::sync_with_stdio(0);cin.tie(0); cout.tie(0);

ll power(ll a, ll b, ll md) {return (!b ? 1 : (b & 1 ? a * power(a * a % md, b / 2, md) % md : power(a * a % md, b / 2, md) % md));}

const int xn = 1e2 + 10;
const int xm = 1e3 + 10;
const int sq = 320;
const int inf = 1e9 + 10;
const ll INF = 1e18 + 10;
const ld eps = 1e-15;
const int mod = 1e9 + 7;//998244353;
const int base = 257;

int n, a[xn], L, dp[xn][xn][2][2][xm], ans;

int main(){
	fast_io;

	cin >> n >> L;
	for (int i = 1; i <= n; ++ i)
		cin >> a[i];
	sort(a + 1, a + n + 1);
	for (int i = 0; i < 2; ++ i)
		for (int j = 0; j < 2; ++ j)
			dp[1][1][i][j][0] = 1;
	for (int i = 1; i < n; ++ i){
		for (int j = 1; j <= i; ++ j){
			for (int f1 = 0; f1 < 2; ++ f1){
				for (int f2 = 0; f2 < 2; ++ f2){
					for (int k = 0; k <= L; ++ k){
						int kp = k + (j + j - 2 + f1 + f2) * (a[i + 1] - a[i]);
						if (L < kp)
							continue;
						dp[i + 1][j][f1][f2][kp] = (dp[i + 1][j][f1][f2][kp] + 1ll * dp[i][j][f1][f2][k] * (j + j - 2) % mod) % mod;
						dp[i + 1][j + 1][f1][f2][kp] = (dp[i + 1][j + 1][f1][f2][kp] + 1ll * dp[i][j][f1][f2][k] * (j - 1) % mod) % mod;
						dp[i + 1][j - 1][f1][f2][kp] = (dp[i + 1][j - 1][f1][f2][kp] + 1ll * dp[i][j][f1][f2][k] * (j - 1) % mod) % mod;
						if (f1){
							for (int f3 = 0; f3 < 2; ++ f3){
								dp[i + 1][j][f3][f2][kp] = (dp[i + 1][j][f3][f2][kp] + dp[i][j][f1][f2][k]) % mod;
								dp[i + 1][j + 1][f3][f2][kp] = (dp[i + 1][j + 1][f3][f2][kp] + dp[i][j][f1][f2][k]) % mod;
							}
						}
						if (f2){
							for (int f3 = 0; f3 < 2; ++ f3){
								dp[i + 1][j][f1][f3][kp] = (dp[i + 1][j][f1][f3][kp] + dp[i][j][f1][f2][k]) % mod;
								dp[i + 1][j + 1][f1][f3][kp] = (dp[i + 1][j + 1][f1][f3][kp] + dp[i][j][f1][f2][k]) % mod;
							}
						}
					}
				}
			}
		}
	}
	for (int i = 0; i <= L; ++ i)
		ans = (ans + dp[n][1][0][0][i]) % mod;
	cout << ans << endl;

	return 0;
}

• Subtask 1: 5 / 5
• Subtask 2: 15 / 15
• Subtask 3: 80 / 80