There are four towns, numbered 1,2,3 and 4. Also, there are three roads. The i-th road connects different towns a_i and b_i bidirectionally. No two roads connect the same pair of towns. Other than these roads, there is no way to travel between these towns, but any town can be reached from any other town using these roads.

Determine if we can visit all the towns by traversing each of the roads exactly once.

Constraints

* 1 \leq a_i,b_i \leq 4(1\leq i\leq 3)
* a_i and b_i are different. (1\leq i\leq 3)
* No two roads connect the same pair of towns.
* Any town can be reached from any other town using the roads.

Input

Input is given from Standard Input in the following format:


a_1 b_1
a_2 b_2
a_3 b_3


Output

If we can visit all the towns by traversing each of the roads exactly once, print `YES`; otherwise, print `NO`.

Examples

Input

4 2
1 3
2 3


Output

YES


Input

3 2
2 4
1 2


Output

NO


Input

2 1
3 2
4 3


Output

YES
import java.util.*;
import java.io.*;

import static java.lang.Math.*;
import static java.util.Arrays.*;
import static java.util.Collections.*;
 
public class Main{
    static final long mod=1000000007;
//    static int dx[]={-1,0,1,0};
//    static int dy[]={0,-1,0,1};

    public  static void main(String[] args)   throws Exception, IOException{        
        Reader sc = new Reader(System.in);
        PrintWriter out=new PrintWriter(System.out);
        // int n=sc.nextInt();
        // char c[][] = new char[h][w];
        // char c[]=sc.nextString().toCharArray();
        // int d[]=new int[n];
        // for(int i=0; i<n; i++) {d[i]=sc.nextInt();}

//        int n=sc.nextInt();
        int d[][]= new int[4][4];
        for (int i = 0; i < 3; i++) {
    		int a=sc.nextInt()-1;
    		int b=sc.nextInt()-1;
    		d[a][b]=d[b][a]=1;
    	}
        String ans = "NO";
        
loop:
        for (int i = 0; i < 4; i++) {
        	int e[]=new int[4];
			for (int j = 0; j < 4; j++) {
				for (int w = 0; w < 4; w++) {
					for (int v = 0; v < 4; v++) {
						if(func(i,j,w,v) && d[i][j]>0 && d[w][j]>0 && d[w][v]>0 )
						{
							ans="YES";break loop;
						}
					}
				}
			}
		}

        out.println(ans);
        out.flush();
    }

    static boolean func(int a,int b,int c,int e) {
    	int d[]=new int[4];
    	d[a]++;
    	d[b]++;
    	d[c]++;
    	d[e]++;
    	sort(d);
    	if(d[0]==1 && d[3]==1)return true;
    	return false;
    }
    
    static boolean validpos(int x,int y,int r, int c){
        return x<r && 0<=x && y<c && 0<=y;
    }

    static void db(Object... os){
        System.err.println(Arrays.deepToString(os));
    }  
}

//class P {
//    int id, d;
//    P(int  id, int d) {
//        this.id=id;
//        this.d=d;
//    }
//}

//class P implements Comparable<P>{
//    int a,b;
//    P(int a, int b) {
//        this.a=a;
//        this.b=b;
//    }
//    public int compareTo(P p){
//        return b-p.b; //des
//    }
//}

class Reader
{ 
    private BufferedReader x;
    private StringTokenizer st;
    
    public Reader(InputStream in)
    {
        x = new BufferedReader(new InputStreamReader(in));
        st = null;
    }
    public String nextString() throws IOException
    {
        while( st==null || !st.hasMoreTokens() )
            st = new StringTokenizer(x.readLine());
        return st.nextToken();
    }
    public int nextInt() throws IOException
    {
        return Integer.parseInt(nextString());
    }
    public int[] nextIntArray(int size) throws IOException{
    	int r[] = new int[size];
    	for (int i = 0; i < size; i++) {
			r[i] = this.nextInt(); 
		}
    	return r;
    }
    public long nextLong() throws IOException
    {
        return Long.parseLong(nextString());
    }
    public double nextDouble() throws IOException
    {
        return Double.parseDouble(nextString());
    }
}
