import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;

public class a {

	private static class Pair implements Comparable<Pair> {
		int f;
		int s;

		Pair(int f, int s) {

			this.f = f;
			this.s = s;
		}

		@Override
		public int compareTo(Pair o) {
			return (f - o.f);
		}

	}
	public static int n;
	public static int m;
	public static boolean visited[][];
	public static long dp[][];

	public static long sol(int i,int j){
	    if(i>n||j>m){
		   return 0;
	   }else if(i==n&&j==m){
		   return 1;
	   }else if(dp[i][j]!=-1){
		   return dp[i][j];
	   }else{
		   long choose1=0;
		   long choose2=0;
		   if((visited[i][j]&&visited[i+1][j])==false){
			   choose1=sol(i+1,j);
		   }
		   if((visited[i][j]&&visited[i][j+1])==false){
			   choose2=sol(i,j+1);
		   }
		   return dp[i][j]=choose1+choose2;
	   }

	}
	public static long numWays(int width, int height, String[] bad){
		n=height;
		m=width;
		visited=new boolean[n+2][m+2];
		for (int i = 0; i < bad.length; i++) {
			String s[]=bad[i].split(" ");
			visited[Integer.parseInt(s[1])][Integer.parseInt(s[0])]=true;
			visited[Integer.parseInt(s[3])][Integer.parseInt(s[2])]=true;

		}
		dp = new long[n+5][m+5];
		for (int i = 0; i < n+5; i++) {
			for (int j = 0; j < m+5; j++) {
				dp[i][j]=-1;
			}
		}
		return sol(0,0);


	}

	public static void main(String[] args) throws IOException {
//		 BufferedReader in = new BufferedReader(new
//		 InputStreamReader(System.in));
//		 PrintWriter out = new PrintWriter(new
//		 OutputStreamWriter(System.out));
//		 String s[] = in.readLine().split(" ");
//		 int[] sequence = new int[s.length];
//		 for (int i = 0; i < s.length; i++) {
//		 sequence[i] = Integer.parseInt(s[i]);
//		 }
//		 out.println(longestZigZag(sequence));
//		 out.close();

        String t[]={"0 0 0 1","6 6 5 6"};
        System.out.println(numWays(6, 6, t));
		String a[] = { };
		System.out.println(numWays(1, 1, a));
		String b[] = { };
		System.out.println(numWays(35, 31, b));
		String c[] = {"0 0 1 0", "1 2 2 2", "1 1 2 1"};
		System.out.println(numWays(2, 2, c));



	}
}