Problem: Arpa is taking a geometry exam. Here is the last problem of the exam.

You are given three points a, b, c.

Find a point and an angle such that if we rotate the page around the point by the angle, the new position of a is the same as the old position of b, and the new position of b is the same as the old position of c.

Arpa is doubting if the problem has a solution or not (i.e. if there exists a point and an angle satisfying the condition). Help Arpa determine if the question has a solution or not.

Input

The only line contains six integers ax, ay, bx, by, cx, cy (|ax|, |ay|, |bx|, |by|, |cx|, |cy| ≤ 109). It's guaranteed that the points are distinct.

Output

Print "Yes" if the problem has a solution, "No" otherwise.

You can print each letter in any case (upper or lower).

Examples

Input

0 1 1 1 1 0


Output

Yes


Input

1 1 0 0 1000 1000


Output

No

Note

In the first sample test, rotate the page around (0.5, 0.5) by <image>.

In the second sample test, you can't find any solution.

Solution (in JAVA):

Solution:
import java.util.*;


import java.awt.Point;
import java.io.*;
import java.math.BigInteger;
public class Solutions {

static int MAX=Integer.MAX_VALUE;
		static int MIN=Integer.MIN_VALUE;
//static ArrayList<ArrayList<Integer>>list=new ArrayList<ArrayList<Integer>>();
	static FastScanner scr=new FastScanner();
	static PrintStream out=new PrintStream(System.out);
	public static void main(String []args) {
//		for(int i=0;i<3;i++) {
			long ax=scr.nextLong();
			long ay=scr.nextLong();
			long bx=scr.nextLong();
			long by=scr.nextLong();
			
			
			long cx=scr.nextLong();
			long cy=scr.nextLong();
			
			 long dx1 = bx-ax;
		     long dy1 = by-ay;
		     long dx2 = cx-bx;
		     long dy2 = cy-by;
		     long crossProduct = dx1*dy2 - dy1*dx2;
		     long dist1 = dx1*dx1 + dy1*dy1;
		     long dist2 = dx2*dx2 + dy2*dy2;
		     boolean ok = (crossProduct != 0) && (dist1 == dist2);
		     System.out.println(ok ? "Yes" : "No");
//		}
	}
	static long modPow(long base,long exp,long mod) {
		if(exp==0) {
			return 1;
		}
		if(exp%2==0) {
			long res=(modPow(base,exp/2,mod));
			return (res*res)%mod;
		}
		return (base*modPow(base,exp-1,mod))%mod;
	}
	static long gcd(long a,long b) {
		if(b==0) {
			return a;
		}
		return gcd(b,a%b);
	}
	static class FastScanner {
		BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
		StringTokenizer st=new StringTokenizer("");
	 	String next() {
	 		while (!st.hasMoreTokens())
	 			try {
	 				st=new StringTokenizer(br.readLine());
	 			} catch (IOException e) {
	 				e.printStackTrace();
	 			}
	 			return st.nextToken();
		}
		int[] sort(int a[]) {
			Arrays.sort(a);
			return a;
		}
		int []reverse(int a[]){
			int b[]=new int[a.length];
			int index=0;
			for(int i=a.length-1;i>=0;i--) {
				b[index]=a[i];
			}
			return b;
		}
		int nextInt() {
			return Integer.parseInt(next());
		}
		int[] readArray(int n) {
			int[] a=new int[n];
			for (int i=0; i<n; i++) a[i]=nextInt();
			return a;
		}
		long[] readLongArray(int n) {
			long  [] a=new long  [n];
			for (int i=0; i<n; i++) a[i]=nextLong();
			return a;
		}
		long nextLong() {
			return Long.parseLong(next());
		}
	}

}
class triplet{
	int x;
	int y;
	int z;
	triplet(int fisrt,int second,int third){
		this.x=fisrt;
		this.y=second;
		this.z=third;
	}
}
class pair{
	int x=0;
	int y=0;
	pair(int first,int second){
		this.x=first;
		this.y=second;
	}
}