Submission #291266

#	Time	Username	Problem	Language	Result	Execution time	Memory
291266		YJU	Skyscraper (JOI16_skyscraper)	C++14	100 / 100	193 ms	81912 KiB

skyscraper

#include<bits/stdc++.h>
#pragma GCC optimize("unroll-loops,no-stack-protector")
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<ll,ll> pll;
const ll MOD=1e9+7;
const ll MOD2=998244353;
const ll N=1e2+5;
const ld pi=3.14159265359;
const ll INF=(1LL<<60);
#define SQ(i) ((i)*(i))
#define REP(i,n) for(ll i=0;i<n;i++)
#define REP1(i,n) for(ll i=1;i<=n;i++)
#define pb push_back
#define mp make_pair
#define X first
#define Y second
#define setp setprecision
#define lwb lower_bound
#define SZ(_a) (ll)_a.size()



void add(ll &A,ll B){
	A=(A+B)%MOD;
	return;
}

ll n,k,u[N],dp[N][N][1005][3],ans;

int main(){
	ios_base::sync_with_stdio(0);cin.tie(0);
	cin>>n>>k;
	REP1(i,n)cin>>u[i];
	sort(u+1,u+n+1);
	dp[1][1][0][0]=dp[1][1][0][2]=1;
	dp[1][1][0][1]=2;
	REP1(i,n-1){
		REP1(j,i){
			REP(cost,k+1){
				REP(ty,3){
					ll price=cost+(u[i+1]-u[i])*(2*j-ty);
					if(price>k)continue;
					add(dp[i+1][j][price][ty],dp[i][j][cost][ty]*(2*j-ty)%MOD);
					add(dp[i+1][j+1][price][ty],dp[i][j][cost][ty]*(j-ty+1)%MOD);
					add(dp[i+1][j-1][price][ty],dp[i][j][cost][ty]*(j-1)%MOD);
					if(ty<2){
						add(dp[i+1][j][price][ty+1],dp[i][j][cost][ty]*(2-ty)%MOD);
						add(dp[i+1][j+1][price][ty+1],dp[i][j][cost][ty]*(2-ty)%MOD);
					}
				}
			}
		}
	}
	REP(i,k+1)add(ans,dp[n][1][i][2]);
	cout<<ans<<"\n";
	return 0;
}

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