import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.NoSuchElementException;
import java.util.Scanner;

public class Main {
	static boolean ans=false;
	public static boolean is_inc_kadomatsu(int a, int b, int c) {
		if(a<b && b>c && a<c) return true;
		if(a>b && b<c && a<c) return true;
		return false;
	}
	public static void dfs(int[] d, int[] ord, boolean[] used, int k) {
		if(k==7) {
			//for(int x:ord) System.out.print(x+" ");
			//System.out.println();
			for(int i=0; i<5; i++) {
				if(!is_inc_kadomatsu(d[ord[i]], d[ord[i+1]], d[ord[i+2]])) {
					return;
				}
			}
			ans=true;
			return;
		}
		for(int i=0; i<7; i++) {
			if(used[i]) continue;
			used[i]=true;
			ord[k]=i;
			dfs(d, ord, used, k+1);
			ord[k]=-1;
			used[i]=false;
		}
	}
	public static void main(String[] args) {
		Scanner scanner = new Scanner(System.in);
		//FastScanner scanner=new FastScanner();
		PrintWriter out = new PrintWriter(System.out);
		int[] d=new int[7];
		for(int i=0; i<7; i++) d[i]=scanner.nextInt();
		int[] ord=new int[7];
		Arrays.fill(ord, -1);
		boolean[] used=new boolean[7];
		dfs(d, ord, used, 0);
		if(ans) out.println("YES");
		else out.println("NO");
		out.close();
		scanner.close();
	}
}

class FastScanner {
	private final InputStream in = System.in;
	private final byte[] buffer = new byte[1024];
	private int ptr = 0;
	private int buflen = 0;

	private boolean hasNextByte() {
		if (ptr < buflen) {
			return true;
		} else {
			ptr = 0;
			try {
				buflen = in.read(buffer);
			} catch (IOException e) {
				e.printStackTrace();
			}
			if (buflen <= 0) {
				return false;
			}
		}
		return true;
	}

	private int readByte() {
		if (hasNextByte())
			return buffer[ptr++];
		else
			return -1;
	}

	private static boolean isPrintableChar(int c) {
		return 33 <= c && c <= 126;
	}

	public boolean hasNext() {
		while (hasNextByte() && !isPrintableChar(buffer[ptr]))
			ptr++;
		return hasNextByte();
	}

	public String next() {
		if (!hasNext())
			throw new NoSuchElementException();
		StringBuilder sb = new StringBuilder();
		int b = readByte();
		while (isPrintableChar(b)) {
			sb.appendCodePoint(b);
			b = readByte();
		}
		return sb.toString();
	}

	public long nextLong() {
		if (!hasNext())
			throw new NoSuchElementException();
		long n = 0;
		boolean minus = false;
		int b = readByte();
		if (b == '-') {
			minus = true;
			b = readByte();
		}
		if (b < '0' || '9' < b) {
			throw new NumberFormatException();
		}
		while (true) {
			if ('0' <= b && b <= '9') {
				n *= 10;
				n += b - '0';
			} else if (b == -1 || !isPrintableChar(b)) {
				return minus ? -n : n;
			} else {
				throw new NumberFormatException();
			}
			b = readByte();
		}
	}

	public int nextInt() {
		long nl = nextLong();
		if (nl < Integer.MIN_VALUE || nl > Integer.MAX_VALUE)
			throw new NumberFormatException();
		return (int) nl;
	}

	public double nextDouble() {
		return Double.parseDouble(next());
	}
}