Submission #391160

#	Time	Username	Problem	Language	Result	Execution time	Memory
391160		Return_0	Skyscraper (JOI16_skyscraper)	C++17	100 / 100	187 ms	79480 KiB

skyscraper

#pragma GCC optimize("Ofast,unroll-loops")
// #pragma comment(linker, "/stack:200000000")
// #pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2,fma,tune=native")

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace std;
using namespace __gnu_pbds;

typedef int ll;
typedef long long lol;
typedef long double ld;
typedef pair <ll, ll> pll;

#ifdef SINA
#define dbg(...) __f(#__VA_ARGS__, __VA_ARGS__)
template <typename Arg1> void __f(const char* name, Arg1&& arg1) { cout << name << " : " << arg1 << std::endl; }
template <typename Arg1, typename... Args> void __f (const char* names, Arg1&& arg1, Args&&... args) {
	const char* comma = strchr(names + 1, ',');cout.write(names, comma - names) << " : " << arg1<<" | ";__f(comma+1, args...); }
#define dbg2(x, j, n) cout<< #x << " : "; output((j), (n), x, 1); cout.flush();
#else
#define dbg(...) 0
#define dbg2(x, j, n) 0
#endif
#define SZ(x) ((ll)((x).size()))
#define File(s, t) freopen(s ".txt", "r", stdin); freopen(t ".txt", "w", stdout);
#define input(j, n, a) for (int _i = (j); _i < (n)+(j); _i++) cin>> a[_i];
#define output(j, n, a, t) for (int _i = (j); _i < (n)+(j); _i++) cout<< a[_i] << (((t) && _i != (n)+(j)-1)? ' ' : '\n');
#define kill(x) return cout<< (x) << endl, 0
#define cl const ll
#define fr first
#define sc second
#define lc (v << 1)
#define rc (lc | 1)
#define mid ((l + r) >> 1)
#define All(x) (x).begin(), (x).end()

cl inf = sizeof(ll) == 4 ? (1e9 + 10) : (3e18), mod = 1e9 + 7, MOD = 998244353;

template <class A,class B> ostream& operator << (ostream& out,const pair<A,B>&a){return out<<'('<<a.first<<", "<<a.second<<')';}
template <class A> ostream& operator << (ostream& out, const vector<A> &a) {
	out<< '['; for (int i = -1; ++i < int(a.size());) out<< a[i] << (i + 1 < int(a.size()) ? ", " : ""); return out<<']'; }
template <class T, typename _t = less <T> > using Tree = tree <T, null_type, _t, rb_tree_tag, tree_order_statistics_node_update>;

cl N = 1e2 + 3, L = 1e3 + 3;

ll a [N], n, mx, ans;
lol dp [N][N][L][3];

int main ()
{
	ios::sync_with_stdio(false); cin.tie(0); cout.tie(0);

	cin>> n >> mx;
	input(0, n, a);
	sort(a, a + n);

	if (n == 1) kill(1);
	dp[0][0][0][0] = 1;

	for (ll i = 0, diff; i < n; i++) {
		diff = a[i] - (i ? a[i - 1] : 0);
		for (ll j = 0; j <= i; j++) for (ll l = 0, x; l <= mx; l++) for (ll t = 0; t <= min(j, 2); t++) {
			x = l + diff * (2 * j - t);
			if (x > mx) continue;

			if (j && t < 2) (dp[i + 1][j][x][t + 1] += dp[i][j][l][t] * (2 - t)) %= mod;

			if (t < 2) (dp[i + 1][j + 1][x][t + 1] += dp[i][j][l][t] * (2 - t)) %= mod;

			if (j > 1) (dp[i + 1][j - 1][x][t] += dp[i][j][l][t] * (j - 1)) %= mod;

			if (j) (dp[i + 1][j][x][t] += dp[i][j][l][t] * (2 * j - t)) %= mod;

			(dp[i + 1][j + 1][x][t] += dp[i][j][l][t] * (j + 1 - t)) %= mod;
		}
	}

	for (ll i = 0; i <= mx; i++) (ans += dp[n][1][i][2]) %= mod;
	kill(ans);

	cerr<< "\nTime elapsed: " << 1000 * clock() / CLOCKS_PER_SEC << "ms\n";

	return 0;
}
/*
4 10
3 6 2 9

8 35
3 7 1 5 10 2 11 6

*/

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