oj.uz

Submission #98307

# Submission time Handle Problem Language Result Execution time Memory
98307 2019-02-22T01:38:33 Z qkxwsm Skyscraper (JOI16_skyscraper) C++14
100 / 100
 1359 ms 100720 KB 
#pragma GCC optimize ("O3")
#pragma GCC target ("sse4")
#include <bits/stdc++.h>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/rope>

using namespace std;
using namespace __gnu_pbds;
using namespace __gnu_cxx;

random_device(rd);
mt19937 rng(rd());
const long long FIXED_RANDOM = chrono::steady_clock::now().time_since_epoch().count();

struct custom_hash
{
	template<class T>
	unsigned long long operator()(T v) const
	{
		unsigned long long x = v;
		x += FIXED_RANDOM;
		// x += 11400714819323198485ull;
		// x = (x ^ (x >> 30)) * 13787848793156543929ull;
		x = (x ^ (x >> 27)) * 10723151780598845931ull;
		return x ^ (x >> 31);
	}
};

template<class T> using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
template<class T, class U> using hash_table = gp_hash_table<T, U, custom_hash>;

template<class T>
T randomize(T mod)
{
	return (uniform_int_distribution<T>(0, mod - 1))(rng);
}
template<class T>
void readi(T &x)
{
	x = 0;
	bool negative = false;
	char c = ' ';
	while (c < '-')
	{
		c = getchar();
	}
	if (c == '-')
	{
		negative = true;
		c = getchar();
	}
	while (c >= '0')
	{
		x = x * 10 + (c - '0');
		c = getchar();
	}
	if (negative)
	{
		x = -x;
	}
}
template<class T>
void printi(T output)
{
	if (output == 0)
	{
		putchar('0');
		return;
	}
	if (output < 0)
	{
		putchar('-');
		output = -output;
	}
	int buf[20], n = 0;
	while(output)
	{
		buf[n] = ((output % 10));
		output /= 10;
		n++;
	}
	for (n--; n >= 0; n--)
	{
		putchar(buf[n] + '0');
	}
	return;
}
template<class T>
void ckmin(T &a, T b)
{
	a = min(a, b);
}
template<class T>
void ckmax(T &a, T b)
{
	a = max(a, b);
}
long long expo(long long a, long long e, long long mod)
{
	return ((e == 0) ? 1 : ((expo(a * a % mod, e >> 1, mod)) * ((e & 1) ? a : 1) % mod));
}
template<class T, class U>
void nmod(T &x, U mod)
{
	if (x >= mod) x -= mod;
}
template<class T>
T gcd(T a, T b)
{
	return (b ? gcd(b, a % b) : a);
}

#define y0 ___y0
#define y1 ___y1
#define MP make_pair
#define PB push_back
#define LB lower_bound
#define UB upper_bound
#define fi first
#define se second
#define DBG(x) cerr << #x << " = " << (x) << endl
#define SZ(x) ((int) ((x).size()))
#define FOR(i, a, b) for (auto i = (a); i < (b); i++)
#define FORD(i, a, b) for (auto i = (a) - 1; i >= (b); i--)
#define ALL(x) (x).begin(), (x).end()

const long double PI = 4.0 * atan(1.0);
const long double EPS = 1e-9;

#define MAGIC 347
#define SINF 10007
#define CO 1000007
#define INF 1000000007
#define BIG 1000000931
#define LARGE 1696969696967ll
#define GIANT 2564008813937411ll
#define LLINF 2696969696969696969ll
#define MAXN 113

typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef pair<ld, ld> pdd;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef vector<ld> vd;
typedef vector<pii> vpi;
typedef vector<pll> vpl;
typedef vector<pdd> vpd;

int N, L;
int arr[MAXN];
hash_table<int, int> dp[MAXN][2][2][MAXN];
int ans;
int states = 0;

int solve(int idx, bool lt, bool rt, int cc, int sum)
{
	if (sum > L) return 0;
	if (idx == N)
	{
		// if (sum <= L && lt == 1 && rt == 1 && cc == 1) DBG(sum);
		// states++;
		return ((sum <= L && lt == 1 && rt == 1 && cc == 1) ? 1 : 0);
	}
	if (dp[idx][lt][rt][cc].find(sum) != dp[idx][lt][rt][cc].end())
	{
		return dp[idx][lt][rt][cc][sum];
	}
	ll res = 0;
	if (!lt)
	{
		//latch onto the left!
		res += solve(idx + 1, 1, rt, cc, sum + arr[idx] - arr[idx] * (cc - 1) * 2 + arr[idx + 1] * (cc - 1) * 2);
		//create a new one on the left!
		res += solve(idx + 1, 1, rt, cc + 1, sum - arr[idx] - arr[idx] * (cc - 1) * 2 + arr[idx + 1] * cc * 2);
	}
	if (!rt)
	{
		//latch onto the right!
		res += solve(idx + 1, lt, 1, cc, sum + arr[idx] - arr[idx] * (cc - 1) * 2 + arr[idx + 1] * (cc - 1) * 2);
		//create a new one on the right!
		res += solve(idx + 1, lt, 1, cc + 1, sum - arr[idx] - arr[idx] * (cc - 1) * 2 + arr[idx + 1] * (cc) * 2);
	}
	//create a new connected component that's by itself!
	res += 1ll * (cc + 1 - lt - rt) * solve(idx + 1, lt, rt, cc + 1, sum - 2 * arr[idx] - arr[idx] * (cc - 1) * 2 + arr[idx + 1] * (cc) * 2);
	//join two connected components!
	if (cc > 1) res += 1ll * (cc - 1) * solve(idx + 1, lt, rt, cc - 1, sum + 2 * arr[idx] - arr[idx] * (cc - 1) * 2 + arr[idx + 1] * (cc - 2) * 2);
	//latch on right or left!
	res += 1ll * (2 * cc - lt - rt) * solve(idx + 1, lt, rt, cc, sum - arr[idx] * (cc - 1) * 2 + arr[idx + 1] * (cc - 1) * 2);
	res %= INF;
	dp[idx][lt][rt][cc][sum] = res;
	// if (res != 0)
	// {
	// 	cerr << sum << endl;
	// }
	if (res != 0) { states++;}
	// cerr << idx << ' ' << lt << ' ' << rt << ' ' << cc << ' ' << sum << ' ' << res << endl;
	return res;
}

int32_t main()
{
	ios_base::sync_with_stdio(0); cin.tie(0);
	// cout << fixed << setprecision(10);
	// cerr << fixed << setprecision(10);
	// if (fopen("file.in", "r"))
	// {
	// 	freopen ("file.in", "r", stdin);
	// 	freopen ("file.out", "w", stdout);
	// }
	cin >> N >> L;
	if (N == 1)
	{
		cout << "1\n";
		return 0;
	}
	FOR(i, 0, N)
	{
		cin >> arr[i];
	}
	sort(arr, arr + N);
	if (arr[N - 1] - arr[0] > L)
	{
		cout << "0\n";
		return 0;
	}
	ans = solve(1, 0, 0, 1, -2 * arr[0]); nmod(ans, INF);
	ans += solve(1, 1, 0, 1, -arr[0]); nmod(ans, INF);
	ans += solve(1, 0, 1, 1, -arr[0]); nmod(ans, INF);
	// DBG(states);
	cout << ans << '\n';
	//when we place a # down, we can either say: ok new left spot open! ok new right spot open! ok new nothing open!
	//dp of:
	//total sum,
	// cerr << "time elapsed = " << (clock() / (CLOCKS_PER_SEC / 1000)) << " ms" << endl;
	return 0;
}
/* READ READ READ
* int overflow, maxn too small, special cases (n=1?, two distinct?), cin.tie() interactive
* reread the problem, try small cases
* note down possible sources of error as you go
* do smth instead of nothing
*/

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 16 ms 11136 KB Output is correct
2 Correct 15 ms 11136 KB Output is correct
3 Correct 15 ms 11128 KB Output is correct
4 Correct 14 ms 11172 KB Output is correct
5 Correct 16 ms 11256 KB Output is correct
6 Correct 21 ms 11264 KB Output is correct
7 Correct 16 ms 11136 KB Output is correct
8 Correct 15 ms 11264 KB Output is correct
9 Correct 17 ms 11236 KB Output is correct
10 Correct 15 ms 11136 KB Output is correct

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 17 ms 11264 KB Output is correct
2 Correct 22 ms 11392 KB Output is correct
3 Correct 16 ms 11264 KB Output is correct
4 Correct 18 ms 11384 KB Output is correct
5 Correct 16 ms 11392 KB Output is correct
6 Correct 20 ms 11472 KB Output is correct
7 Correct 17 ms 11264 KB Output is correct
8 Correct 18 ms 11264 KB Output is correct
9 Correct 17 ms 11392 KB Output is correct
10 Correct 17 ms 11392 KB Output is correct

Subtask #3
80.0 / 80.0

# Verdict Execution time Memory Grader output
1 Correct 16 ms 11136 KB Output is correct
2 Correct 15 ms 11136 KB Output is correct
3 Correct 15 ms 11128 KB Output is correct
4 Correct 14 ms 11172 KB Output is correct
5 Correct 16 ms 11256 KB Output is correct
6 Correct 21 ms 11264 KB Output is correct
7 Correct 16 ms 11136 KB Output is correct
8 Correct 15 ms 11264 KB Output is correct
9 Correct 17 ms 11236 KB Output is correct
10 Correct 15 ms 11136 KB Output is correct
11 Correct 17 ms 11264 KB Output is correct
12 Correct 22 ms 11392 KB Output is correct
13 Correct 16 ms 11264 KB Output is correct
14 Correct 18 ms 11384 KB Output is correct
15 Correct 16 ms 11392 KB Output is correct
16 Correct 20 ms 11472 KB Output is correct
17 Correct 17 ms 11264 KB Output is correct
18 Correct 18 ms 11264 KB Output is correct
19 Correct 17 ms 11392 KB Output is correct
20 Correct 17 ms 11392 KB Output is correct
21 Correct 20 ms 11904 KB Output is correct
22 Correct 1359 ms 100720 KB Output is correct
23 Correct 772 ms 73820 KB Output is correct
24 Correct 813 ms 80852 KB Output is correct
25 Correct 741 ms 73856 KB Output is correct
26 Correct 689 ms 70724 KB Output is correct
27 Correct 276 ms 34016 KB Output is correct
28 Correct 455 ms 48736 KB Output is correct
29 Correct 923 ms 83644 KB Output is correct
30 Correct 824 ms 76172 KB Output is correct