oj.uz

Submission #565187

# Submission time Handle Problem Language Result Execution time Memory
565187 2022-05-20T12:27:49 Z errorgorn Fences (JOI18_fences) C++17
51 / 100
 916 ms 2004 KB 
#include <bits/stdc++.h>
using namespace std;

#define int long long
#define ii pair<int,int>
#define fi first
#define se second

#define puf push_front
#define pof pop_front
#define pub push_back
#define pob pop_back
#define lb lower_bound
#define ub upper_bound

#define rep(x,s,e) for (int x=(s)-((s)>(e));x!=(e)-((s)>(e));((s)<(e))?x++:x--)
#define all(x) (x).begin(),(x).end()
#define sz(x) (int) (x).size()

mt19937 rng(chrono::system_clock::now().time_since_epoch().count());

const double EPS=1e-9;
const double TAU=acos(0)*4;

struct vec{
	double x,y;
};

vec add(vec i,vec j){
	return {i.x+j.x,i.y+j.y};
}

vec sub(vec i,vec j){
	return {i.x-j.x,i.y-j.y};
};

vec mul(double lambda,vec i){
	return {i.x*lambda,i.y*lambda};
};

double dist(vec i,vec j){
	double dx=i.x-j.x;
	double dy=i.y-j.y;
	return sqrt(dx*dx+dy*dy);
}

int n;
double k;
int arr[110][4];

vector<vec> p; //stores all points
vector<double> angle;

double diff(double i,double j){
	double res=i-j;
	while (res<-TAU/2) res+=TAU;
	while (res>TAU/2) res-=TAU;
	return res;
}

int count(double i){
	return floor(i/TAU+0.5);
}

#define id pair<int,double>
#define dii pair<double,ii>
double w[10005][5];
vector<id> al[10005];

priority_queue<dii,vector<dii>,greater<dii> > pq;

bool inter(vec i,vec j,vec a,vec b){
	//i.x + j.x*L1 = a.x + b.x*L2
	//i.y + j.y*L1 = a.y + b.y*L2
	
	//j.x * L1 - b.x * L2 = a.x - i.x
	//j.y * L1 - b.y * L2 = a.y - i.y
	
	//check that L1,L2 in [0,1]
	
	vector<double> v = {
		a.x - i.x,
		a.y - i.y
	};
	
	vector<vector<double> > mat = {
		{j.x,-b.x},
		{j.y,-b.y}
	};
	
	double det=mat[0][0]*mat[1][1]-mat[0][1]*mat[1][0];
	if (abs(det)<=1e-9) return false;
	
	vector<vector<double> > imat = {
		{mat[1][1],-mat[0][1]},
		{-mat[1][0],mat[0][0]}
	};
	rep(x,0,2) rep(y,0,2) imat[x][y]/=det;
	
	rep(x,0,2){
		double res=0;
		rep(y,0,2){
			res+=imat[x][y]*v[y];
		}
		if (res<0 || 1<res) return false;
	}
	return true;
}

bool ok(vec i,vec j){
	vector<vec> v={  {-k+2*EPS,-k+EPS},{-k+EPS,k-2*EPS},{k-2*EPS,k-EPS},{k-EPS,-k+2*EPS} };
	vector<vec> v2={ {-k+2*EPS,k-EPS},{k-EPS,k-2*EPS},{k-2*EPS,-k+EPS},{-k+EPS,-k+2*EPS} };
	
	rep(x,0,4){
		if (inter(i,sub(j,i),v[x],sub(v2[x],v[x]))) return false;
	}
	return true;
}

signed main(){
	cin.tie(0);
	cout.tie(0);
	cin.sync_with_stdio(false);
	
	cin>>n>>k;
	rep(x,0,n) rep(y,0,4) cin>>arr[x][y];
	rep(x,0,4) rep(y,0,4){
		if (x==3 || (x && (x+y)%2==0)) arr[n+x][y]=-k;
		else arr[n+x][y]=k;
	}
	n+=4;
	
	//rep(x,0,n){
		//rep(y,0,4) cout<<arr[x][y]<<" "; cout<<endl;
	//}
	
	rep(x,0,n) p.pub({(double)arr[x][0],(double)arr[x][1]});
	rep(x,0,n) p.pub({(double)arr[x][2],(double)arr[x][3]});
	rep(x,0,n){
		al[x].pub({x+n,0});
		al[x+n].pub({x,0});
	}
	
	double ans=8*k;
	
	rep(x,0,n) rep(y,x+1,n){
		vec temp[4];
		vec temp2[4];
		
		double best=1e18;
		int idx=-1;
		
		rep(z,0,4){
			if (z>=2) swap(x,y);
			
			if (z%2==0) temp2[z]=p[x];
			else temp2[z]=p[x+n];
			
			vec base=p[y];
			vec dir=sub(p[y+n],p[y]);
			
			double lo=0,hi=1;
			rep(x,0,150){
				double mi1=lo+(hi-lo)/3,mi2=lo+2*(hi-lo)/3;
				
				if (dist(add(base,mul(mi1,dir)),temp2[z])<dist(add(base,mul(mi2,dir)),temp2[z])){
					hi=mi2;
				}
				else{
					lo=mi1;
				}
			}
			
			temp[z]=add(base,mul(lo,dir));
			double curr=dist(temp2[z],temp[z]);
			if (curr<best){
				best=curr;
				idx=z;
			}
			
			if (z>=2) swap(x,y);
		}
		
		if (ok(temp[idx],temp2[idx])){
			//cout<<x<<" "<<y<<" "<<best<<" "<<idx<<endl;
			//cout<<temp[idx].x<<" "<<temp[idx].y<<endl;
			//cout<<temp2[idx].x<<" "<<temp2[idx].y<<endl;
			//rep(z,0,4) cout<<arr[x][z]<<" "; cout<<endl;
			//rep(z,0,4) cout<<arr[y][z]<<" "; cout<<endl;
			//cout<<endl;
			
			//cout<<"cunny"<<endl;
			int IDX1=sz(p),IDX2;
			p.pub(temp[idx]);
			
			if (idx==0) IDX2=x;
			if (idx==1) IDX2=x+n;
			if (idx==2) IDX2=y;
			if (idx==3) IDX2=y+n;
			
			//cout<<temp2[idx].x<<" "<<temp2[idx].y<<endl;
			//cout<<p[IDX2].x<<" "<<p[IDX2].y<<endl;
			
			al[IDX1].pub({IDX2,best});
			al[IDX2].pub({IDX1,best});
			
			if (idx<2) IDX2=y;
			else IDX2=x;
			al[IDX1].pub({IDX2,0});
			al[IDX2].pub({IDX1,0});
		}
	}
	
	rep(x,0,sz(p)){
		angle.pub(atan2(p[x].x,p[x].y)+TAU/2);
		//cout<<x<<" "<<p[x].x<<" "<<p[x].y<<" "<<angle[x]<<endl;
	}
	
	rep(x,0,n){
		rep(y,0,sz(p)) rep(z,0,5) w[y][z]=1e18;
		
		w[x][2]=0;
		pq.push({w[x][2],ii(x,2)});
		
		while (!pq.empty()){
			double weight;
			ii u;
			tie(weight,u)=pq.top(),pq.pop();
			if (w[u.fi][u.se]!=weight) continue;
			
			double angle1=diff(angle[x],angle[u.fi])+TAU*u.se;
			
			for (auto [it,w2]:al[u.fi]){
				int it2=count(angle1+diff(angle[u.fi],angle[it])-diff(angle[x],angle[it]));
				if (it2<0 || 4<it2) continue;
				if (w[it][it2]>weight+w2){
					w[it][it2]=weight+w2;
					pq.push({w[it][it2],ii(it,it2)});
				}
			}
		}
		
		//cout<<x<<" "<<w[x][3]<<endl;
		ans=min(ans,w[x][3]);
	}
	
	cout<<fixed<<setprecision(12)<<ans<<endl;
}

Subtask #1
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 468 KB Output is correct
2 Correct 1 ms 468 KB Output is correct
3 Correct 1 ms 468 KB Output is correct
4 Correct 1 ms 468 KB Output is correct
5 Correct 1 ms 468 KB Output is correct
6 Correct 1 ms 468 KB Output is correct
7 Correct 1 ms 468 KB Output is correct
8 Correct 1 ms 468 KB Output is correct
9 Correct 1 ms 468 KB Output is correct
10 Correct 1 ms 468 KB Output is correct
11 Correct 1 ms 468 KB Output is correct
12 Correct 1 ms 468 KB Output is correct
13 Correct 1 ms 468 KB Output is correct
14 Correct 1 ms 468 KB Output is correct
15 Correct 1 ms 468 KB Output is correct
16 Correct 1 ms 468 KB Output is correct
17 Correct 1 ms 468 KB Output is correct
18 Correct 1 ms 468 KB Output is correct
19 Correct 1 ms 468 KB Output is correct
20 Correct 1 ms 468 KB Output is correct

Subtask #2
33.0 / 33.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 468 KB Output is correct
2 Correct 1 ms 468 KB Output is correct
3 Correct 1 ms 468 KB Output is correct
4 Correct 1 ms 468 KB Output is correct
5 Correct 1 ms 468 KB Output is correct
6 Correct 1 ms 468 KB Output is correct
7 Correct 1 ms 468 KB Output is correct
8 Correct 1 ms 468 KB Output is correct
9 Correct 1 ms 468 KB Output is correct
10 Correct 1 ms 468 KB Output is correct
11 Correct 1 ms 468 KB Output is correct
12 Correct 1 ms 468 KB Output is correct
13 Correct 1 ms 468 KB Output is correct
14 Correct 1 ms 468 KB Output is correct
15 Correct 1 ms 468 KB Output is correct
16 Correct 1 ms 468 KB Output is correct
17 Correct 1 ms 468 KB Output is correct
18 Correct 1 ms 468 KB Output is correct
19 Correct 1 ms 468 KB Output is correct
20 Correct 1 ms 468 KB Output is correct
21 Correct 1 ms 468 KB Output is correct
22 Correct 2 ms 468 KB Output is correct
23 Correct 1 ms 468 KB Output is correct
24 Correct 1 ms 468 KB Output is correct
25 Correct 2 ms 468 KB Output is correct
26 Correct 2 ms 468 KB Output is correct
27 Correct 2 ms 468 KB Output is correct
28 Correct 2 ms 468 KB Output is correct
29 Correct 2 ms 468 KB Output is correct
30 Correct 2 ms 468 KB Output is correct
31 Correct 2 ms 468 KB Output is correct
32 Correct 2 ms 468 KB Output is correct
33 Correct 2 ms 468 KB Output is correct
34 Correct 2 ms 468 KB Output is correct
35 Correct 2 ms 468 KB Output is correct
36 Correct 2 ms 584 KB Output is correct
37 Correct 1 ms 468 KB Output is correct
38 Correct 1 ms 468 KB Output is correct
39 Correct 2 ms 468 KB Output is correct
40 Correct 1 ms 468 KB Output is correct
41 Correct 1 ms 468 KB Output is correct
42 Correct 1 ms 468 KB Output is correct
43 Correct 1 ms 468 KB Output is correct

Subtask #3
0 / 49.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 468 KB Output is correct
2 Correct 1 ms 468 KB Output is correct
3 Correct 1 ms 468 KB Output is correct
4 Correct 1 ms 468 KB Output is correct
5 Correct 1 ms 468 KB Output is correct
6 Correct 1 ms 468 KB Output is correct
7 Correct 1 ms 468 KB Output is correct
8 Correct 1 ms 468 KB Output is correct
9 Correct 1 ms 468 KB Output is correct
10 Correct 1 ms 468 KB Output is correct
11 Correct 1 ms 468 KB Output is correct
12 Correct 1 ms 468 KB Output is correct
13 Correct 1 ms 468 KB Output is correct
14 Correct 1 ms 468 KB Output is correct
15 Correct 1 ms 468 KB Output is correct
16 Correct 1 ms 468 KB Output is correct
17 Correct 1 ms 468 KB Output is correct
18 Correct 1 ms 468 KB Output is correct
19 Correct 1 ms 468 KB Output is correct
20 Correct 1 ms 468 KB Output is correct
21 Correct 1 ms 468 KB Output is correct
22 Correct 2 ms 468 KB Output is correct
23 Correct 1 ms 468 KB Output is correct
24 Correct 1 ms 468 KB Output is correct
25 Correct 2 ms 468 KB Output is correct
26 Correct 2 ms 468 KB Output is correct
27 Correct 2 ms 468 KB Output is correct
28 Correct 2 ms 468 KB Output is correct
29 Correct 2 ms 468 KB Output is correct
30 Correct 2 ms 468 KB Output is correct
31 Correct 2 ms 468 KB Output is correct
32 Correct 2 ms 468 KB Output is correct
33 Correct 2 ms 468 KB Output is correct
34 Correct 2 ms 468 KB Output is correct
35 Correct 2 ms 468 KB Output is correct
36 Correct 2 ms 584 KB Output is correct
37 Correct 1 ms 468 KB Output is correct
38 Correct 1 ms 468 KB Output is correct
39 Correct 2 ms 468 KB Output is correct
40 Correct 1 ms 468 KB Output is correct
41 Correct 1 ms 468 KB Output is correct
42 Correct 1 ms 468 KB Output is correct
43 Correct 1 ms 468 KB Output is correct
44 Correct 916 ms 1964 KB Output is correct
45 Correct 737 ms 1764 KB Output is correct
46 Correct 586 ms 1396 KB Output is correct
47 Correct 445 ms 1232 KB Output is correct
48 Correct 896 ms 2004 KB Output is correct
49 Correct 820 ms 1852 KB Output is correct
50 Correct 607 ms 1372 KB Output is correct
51 Correct 456 ms 1136 KB Output is correct
52 Correct 600 ms 1504 KB Output is correct
53 Correct 578 ms 1380 KB Output is correct
54 Correct 635 ms 1464 KB Output is correct
55 Correct 673 ms 1672 KB Output is correct
56 Correct 701 ms 1700 KB Output is correct
57 Correct 549 ms 1312 KB Output is correct
58 Correct 578 ms 1400 KB Output is correct
59 Correct 607 ms 1400 KB Output is correct
60 Correct 629 ms 1416 KB Output is correct
61 Correct 733 ms 1704 KB Output is correct
62 Correct 4 ms 640 KB Output is correct
63 Correct 3 ms 596 KB Output is correct
64 Correct 584 ms 1476 KB Output is correct
65 Correct 594 ms 1320 KB Output is correct
66 Correct 425 ms 1076 KB Output is correct
67 Incorrect 799 ms 1900 KB Output isn't correct
68 Halted 0 ms 0 KB -