Problem: One warm and sunny day king Copa decided to visit the shooting gallery, located at the Central Park, and try to win the main prize — big pink plush panda. The king is not good at shooting, so he invited you to help him.

The shooting gallery is an infinite vertical plane with Cartesian coordinate system on it. The targets are points on this plane. Each target is described by it's coordinates xi, and yi, by the time of it's appearance ti and by the number pi, which gives the probability that Copa hits this target if he aims at it.

A target appears and disappears instantly, so Copa can hit the target only if at the moment ti his gun sight aimed at (xi, yi). Speed of movement of the gun sight on the plane is equal to 1. Copa knows all the information about the targets beforehand (remember, he is a king!). He wants to play in the optimal way, which maximizes the expected value of the amount of hit targets. He can aim at any target at the moment 0.

Input

The first line contains integer n (1 ≤ n ≤ 1000) — amount of targets in the shooting gallery. Then n lines follow, each describing one target. Each description consists of four numbers xi, yi, ti, pi (where xi, yi, ti — integers,  - 1000 ≤ xi, yi ≤ 1000, 0 ≤ ti ≤ 109, real number pi is given with no more than 6 digits after the decimal point, 0 ≤ pi ≤ 1). No two targets may be at the same point.

Output

Output the maximum expected value of the amount of targets that was shot by the king. Your answer will be accepted if it differs from the correct answer by not more than 10 - 6.

Examples

Input

1
0 0 0 0.5


Output

0.5000000000


Input

2
0 0 0 0.6
5 0 5 0.7


Output

1.3000000000

Solution (in JAVA):

Solution:
import java.io.*;
import java.util.*;
import java.math.*;
import java.math.BigInteger; 
//import javafx.util.*; 
public final class B
{    
	static PrintWriter out = new PrintWriter(System.out); 
	static StringBuilder ans=new StringBuilder();
	static FastReader in=new FastReader();
	static ArrayList<Integer> g[],og[];
	static long mod=(long)(1e9+7);
	static int D1[],D2[],par[];
	static boolean set[];
	static int value[];
	static long INF=Long.MAX_VALUE;
	static int N,M;
	static int val[],tot[],max[];
	static int min;
	static int dp1[][],dp2[][],path1[][],path2[][],two[][],five[][];
	static int path[][],A[];
	static char X[];
	static int sum[];
	public static void main(String args[])throws IOException
	{
		int N=i();
		double dp[]=new double[N];
		node A[]=new node[N];
		double max=0;
		for(int i=0; i<N; i++)
		{
			A[i]=new node(l(),l(),l(),in.nextDouble());
			max=Math.max(A[i].p, max);
		}
		Arrays.sort(A);
		for(int i=0; i<N; i++)dp[i]=A[i].p;
		for(int i=0; i<N; i++)
		{
			for(int j=i+1; j<N; j++)
			{
				
					double d=d(A[j].x,A[j].y,A[i].x,A[i].y);
					long time=A[j].t-A[i].t;
					//System.out.println("for--> i "+i+" j--> "+j+ " t--> "+time+" d--> "+d);
					if(time>=d)
					{
						dp[j]=Math.max(dp[i]+A[j].p, dp[j]);
					}
				
				max=Math.max(max, dp[j]);

			}
//			for(double a:dp)System.out.print(a+" ");
//			System.out.println();
			//print(dp);

		}
		out.println(max);
		out.close();
	}
	static double d(long a,long b,long c,long d)
	{
		long x=(a-c);
		long y=(b-d);
		x*=x;
		y*=y;
		return Math.sqrt(x+y);
	}
	static String add(char A[],char B[])
	{
		StringBuilder sb=new StringBuilder();
		return sb.toString();
	}
	static int f(int N,int v)
	{
		//System.out.println("for--> "+v);
		if(v>N)return 1;
		char ch=X[v];		
		if(sum[v]==-1)
		{
			if(ch=='?')
			{
				return sum[v]=f(N,2*v)+f(N,2*v+1);
			}
			else if(ch=='1')
			{
				return sum[v]=f(N,2*v);
			}
			else
			{
				return sum[v]=f(N,2*v+1);
			}
		}
		return sum[v];
	}
	static void update(int N,int v)
	{
		if(v<1)return ;
		if(X[v]=='?')
		{
			sum[v]=f(N,v*2)+f(N,v*2+1);
		}
		else if(X[v]=='1')sum[v]=f(N,v*2);
		else sum[v]=f(N,2*v+1);
		//System.out.println("sum--> "+v+ " "+sum[v]);
		update(N,v/2);
	}
	static boolean isPalin(char X[])
	{
		int l=0,r=X.length-1;
		while(l<=r)
		{
			if(X[l]!=X[r])return false;
			l++;
			r--;
		}
		return true;
	}

	static boolean isSorted(int A[])
	{
		int N=A.length;
		for(int i=0; i<N-1; i++)
		{
			if(A[i]>A[i+1])return false;
		}

		return true;		
	}
	static int f1(int x,ArrayList<Integer> A)
	{
		int l=-1,r=A.size();
		while(r-l>1)
		{
			int m=(l+r)/2;
			int a=A.get(m);
			if(a<x)l=m;
			else r=m;
		}		
		return l;
	}


	static int ask(int t,int i,int j,int x)
	{
		System.out.println("? "+t+" "+i+" "+j+" "+x);
		return i();
	}

	static int ask(int a)
	{
		System.out.println("? 1 "+a);
		return i();
	}

	static int max(int a,int b,int c)
	{
		return Math.max(a, Math.max(c, b));
	}
	static int value(char X[],char Y[])
	{
		int c=0;
		for(int i=0; i<7; i++)
		{
			if(Y[i]=='1' && X[i]=='0')return -1;
			if(X[i]=='1' && Y[i]=='0')c++;
		}
		return c;
	}
	static boolean isValid(int i,int j)
	{
		if(i<0 || i>=N)return false;
		if(j<0 || j>=M)return false;
		return true;
	}

	static long fact(long N)
	{
		long num=1L;
		while(N>=1)
		{
			num=((num%mod)*(N%mod))%mod;
			N--;
		}
		return num;
	}
	static boolean reverse(long A[],int l,int r)
	{
		while(l<r)
		{
			long t=A[l];
			A[l]=A[r];
			A[r]=t;
			l++;
			r--;
		}
		if(isSorted(A))return true;
		else return false;
	}
	static boolean isSorted(long A[])
	{
		for(int i=1; i<A.length; i++)if(A[i]<A[i-1])return false;
		return true;
	}
	static boolean isPalindrome(char X[],int l,int r)
	{
		while(l<r)
		{
			if(X[l]!=X[r])return false;
			l++; r--;
		}
		return true;
	}

	static long min(long a,long b,long c)
	{
		return Math.min(a, Math.min(c, b));
	}

	static void print(int a)
	{
		System.out.println("! "+a);
	}
	static int ask(int a,int b)
	{
		System.out.println("? "+a+" "+b);
		return i();
	}
	static int find(int a)
	{
		if(par[a]<0)return a;
		return par[a]=find(par[a]);
	}
	static void union(int a,int b)
	{
		a=find(a);
		b=find(b);
		if(a!=b)
		{
			par[a]+=par[b]; //transfers the size
			par[b]=a;       //changes the parent
		}
	}
	static void swap(char A[],int a,int b)
	{
		char ch=A[a];
		A[a]=A[b];
		A[b]=ch;
	}

	static void sort(long[] a) //check for long
	{
		ArrayList<Long> l=new ArrayList<>();
		for (long i:a) l.add(i);
		Collections.sort(l);
		for (int i=0; i<a.length; i++) a[i]=l.get(i);
	}
	static void setGraph(int N)
	{
		g=new ArrayList[N+1];		
		og=new ArrayList[N+1];

		val=new int[N+1];
		for(int i=0; i<=N; i++)
		{
			og[i]=new ArrayList<Integer>();			
			g[i]=new ArrayList<Integer>();
		}
	}

	static  long pow(long a,long b)
	{
		long mod=1000000007;
		long pow=1;
		long x=a;
		while(b!=0)
		{
			if((b&1)!=0)pow=(pow*x)%mod;
			x=(x*x)%mod;
			b/=2;
		}
		return pow;
	}
	static long toggleBits(long x)//one's complement || Toggle bits
	{
		int n=(int)(Math.floor(Math.log(x)/Math.log(2)))+1;

		return ((1<<n)-1)^x;
	}
	static int countBits(long a)
	{
		return (int)(Math.log(a)/Math.log(2)+1);
	}
	static void sort(int[] a) {
		ArrayList<Integer> l=new ArrayList<>();
		for (int i:a) l.add(i);
		Collections.sort(l);
		for (int i=0; i<a.length; i++) a[i]=l.get(i);
	}
	static boolean isPrime(long N)
	{
		if (N<=1)  return false; 
		if (N<=3)  return true; 
		if (N%2 == 0 || N%3 == 0) return false; 
		for (int i=5; i*i<=N; i=i+6) 
			if (N%i == 0 || N%(i+2) == 0) 
				return false; 
		return true; 
	}
	static long GCD(long a,long b) 
	{
		if(b==0)
		{
			return a;
		}
		else return GCD(b,a%b );
	}

	//Debugging Functions Starts

	static void print(char A[])
	{
		for(char c:A)System.out.print(c+" ");
		System.out.println();
	}
	static void print(boolean A[])
	{
		for(boolean c:A)System.out.print(c+" ");
		System.out.println();
	}
	static void print(int A[])
	{
		for(int a:A)System.out.print(a+" ");
		System.out.println();	
	}
	static void print(long A[])
	{
		for(long i:A)System.out.print(i+ " ");
		System.out.println();

	}
	static void print(ArrayList<Integer> A)
	{
		for(int a:A)System.out.print(a+" ");
		System.out.println();
	}

	//Debugging Functions END
	//----------------------
	//IO FUNCTIONS STARTS
	static HashMap<Integer,Integer> Hash(int A[])
	{
		HashMap<Integer,Integer> mp=new HashMap<>();
		for(int a:A)
		{
			int f=mp.getOrDefault(a,0)+1;
			mp.put(a, f);
		}
		return mp;
	}
	static int i()
	{
		return in.nextInt();
	}

	static long l()
	{
		return in.nextLong();
	}

	static int[] input(int N){
		int A[]=new int[N];
		for(int i=0; i<N; i++)
		{
			A[i]=in.nextInt();
		}
		return A;
	}

	static long[] inputLong(int N)     {
		long A[]=new long[N];
		for(int i=0; i<A.length; i++)A[i]=in.nextLong();
		return A;
	}

	//IO FUNCTIONS END

}

class node implements Comparable<node>
{
	long x,y,t;
	double p;
	node(long x,long y,long t,double p)
	{
		this.x=x;
		this.y=y;
		this.t=t;
		this.p=p;
	}
	public int compareTo(node x)
	{
		if(this.t<x.t)return -1;
		if(this.t>x.t)return 1;			
		return 0;
	}

}

//Code For FastReader
//Code For FastReader
//Code For FastReader
//Code For FastReader
class FastReader
{
	BufferedReader br;
	StringTokenizer st;
	public FastReader()
	{
		br=new BufferedReader(new InputStreamReader(System.in));
	}

	String next()
	{
		while(st==null || !st.hasMoreElements())
		{
			try
			{
				st=new StringTokenizer(br.readLine());
			}
			catch(IOException e)
			{
				e.printStackTrace();
			}
		}
		return st.nextToken();
	}

	int nextInt()
	{
		return Integer.parseInt(next());
	}

	long nextLong()
	{
		return Long.parseLong(next());
	}
	//gey
	double nextDouble()
	{
		return Double.parseDouble(next());
	}

	String nextLine()
	{
		String str="";
		try
		{
			str=br.readLine();
		}
		catch (IOException e)
		{
			e.printStackTrace();
		}
		return str;
	}

}