제출 #250713

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
250713		alishahali1382	Skyscraper (JOI16_skyscraper)	C++14	100 / 100	70 ms	35064 KiB

skyscraper

#include <bits/stdc++.h>
#pragma GCC optimize ("O2,unroll-loops")
//#pragma GCC optimize("no-stack-protector,fast-math")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")

using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<pii, int> piii;
typedef pair<ll, ll> pll;
#define debug(x) cerr<<#x<<'='<<(x)<<endl;
#define debugp(x) cerr<<#x<<"= {"<<(x.first)<<", "<<(x.second)<<"}"<<endl;
#define debug2(x, y) cerr<<"{"<<#x<<", "<<#y<<"} = {"<<(x)<<", "<<(y)<<"}"<<endl;
#define debugv(v) {cerr<<#v<<" : ";for (auto x:v) cerr<<x<<' ';cerr<<endl;}
#define all(x) x.begin(), x.end()
#define pb push_back
#define kill(x) return cout<<x<<'\n', 0;

const int inf=1000000010;
const ll INF=10000000000000010LL;
const int mod=1000000007;
const int N=105, L=1005;

int n, k, u, v, x, y, t, a, b;
ll dp[N][N][3][L], ans;
int A[N], B[N];

inline void fix(ll &x){
	if (x>=mod) x-=mod;
	if (x<0) x+=mod;
}

int main(){
	ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
	//freopen("input.txt", "r", stdin);
	//freopen("output.txt", "w", stdout);
	cin>>n>>k;
	if (n==1) kill(1)
	for (int i=1; i<=n; i++) cin>>A[i];
	sort(A+1, A+n+1, [](int i, int j){
		return i>j;
	});
	if (A[1]-A[n]>k) kill(0)
	for (int i=1; i<=n; i++) B[i]=A[i]-A[i+1];
	
	dp[1][0][0][0]=1;
	dp[1][0][1][B[1]]=2;
	if (2*B[1]<=k) dp[1][0][2][2*B[1]]=1;
	for (int i=2; i<=n; i++){
		for (int j=0; j<i; j++) for (int t:{0, 1, 2}){
			for (int s=0; s<=k; s++) if (dp[i-1][j][t][s]){
//				if (s<=6) cerr<<"i="<<i-1<<"  j="<<j<<"  t="<<t<<"  s="<<s<<"    "<<dp[i-1][j][t][s]<<"\n";
				dp[i-1][j][t][s]%=mod;
				if (j){
					dp[i][j+1][t][min(k+1, s+(2*j+t+2)*B[i])]+=j*dp[i-1][j][t][s];
					dp[i][j][t][min(k+1, s+(2*j+t)*B[i])]+=2*j*dp[i-1][j][t][s];
					dp[i][j-1][t][min(k+1, s+(2*j+t-2)*B[i])]+=j*dp[i-1][j][t][s];
				}
				if (t){
					dp[i][j+1][t][min(k+1, s+(2*j+t+2)*B[i])]+=t*dp[i-1][j][t][s];
					dp[i][j][t][min(k+1, s+(2*j+t)*B[i])]+=t*dp[i-1][j][t][s];
					dp[i][j+1][t-1][min(k+1, s+(2*j+t+1)*B[i])]+=t*dp[i-1][j][t][s];
					dp[i][j][t-1][min(k+1, s+(2*j+t-1)*B[i])]+=t*dp[i-1][j][t][s];
				}
			}
		}
	}
	for (int s=0; s<=k; s++) ans=(ans + dp[n][0][0][s])%mod;
	cout<<ans<<"\n";
	
//	debug(dp[2][1][0][6]) // should be 0
	
	return 0;
}
/*
4 10
9 6 3 2



*/

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