import java.util.*;

public class Main {

	public static void main(String args[]) {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int m = sc.nextInt();
		
		boolean[] isSafe=new boolean[n+1];
		Arrays.fill(isSafe, true);
		
		for(int i=0;i<m;i++) {
			isSafe[sc.nextInt()]=false;
		}
		long dp[] = new long[n+1];
		Arrays.fill(dp, 0);
		dp[0]=1;
		dp[1]=1;
		if(!isSafe[1]) dp[1]=0;
		for(int i=2;i<n+1;i++) {
			if(!isSafe[i])continue;
			dp[i]=(dp[i-1]+dp[i-2])%1000000007;
					 
		}
		System.out.println(dp[n]);
	}
} import java.util.*; util.* java public class Main {

	public static void main(String args[]) {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int m = sc.nextInt();
		
		boolean[] isSafe=new boolean[n+1];
		Arrays.fill(isSafe, true);
		
		for(int i=0;i<m;i++) {
			isSafe[sc.nextInt()]=false;
		}
		long dp[] = new long[n+1];
		Arrays.fill(dp, 0);
		dp[0]=1;
		dp[1]=1;
		if(!isSafe[1]) dp[1]=0;
		for(int i=2;i<n+1;i++) {
			if(!isSafe[i])continue;
			dp[i]=(dp[i-1]+dp[i-2])%1000000007;
					 
		}
		System.out.println(dp[n]);
	}
} Main public static void main(String args[]) {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int m = sc.nextInt();
		
		boolean[] isSafe=new boolean[n+1];
		Arrays.fill(isSafe, true);
		
		for(int i=0;i<m;i++) {
			isSafe[sc.nextInt()]=false;
		}
		long dp[] = new long[n+1];
		Arrays.fill(dp, 0);
		dp[0]=1;
		dp[1]=1;
		if(!isSafe[1]) dp[1]=0;
		for(int i=2;i<n+1;i++) {
			if(!isSafe[i])continue;
			dp[i]=(dp[i-1]+dp[i-2])%1000000007;
					 
		}
		System.out.println(dp[n]);
	} main {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int m = sc.nextInt();
		
		boolean[] isSafe=new boolean[n+1];
		Arrays.fill(isSafe, true);
		
		for(int i=0;i<m;i++) {
			isSafe[sc.nextInt()]=false;
		}
		long dp[] = new long[n+1];
		Arrays.fill(dp, 0);
		dp[0]=1;
		dp[1]=1;
		if(!isSafe[1]) dp[1]=0;
		for(int i=2;i<n+1;i++) {
			if(!isSafe[i])continue;
			dp[i]=(dp[i-1]+dp[i-2])%1000000007;
					 
		}
		System.out.println(dp[n]);
	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int n = sc.nextInt(); n sc.nextInt() sc.nextInt sc int m = sc.nextInt(); m sc.nextInt() sc.nextInt sc boolean[] isSafe=new boolean[n+1]; isSafe new boolean[n+1] n+1 n 1 Arrays.fill(isSafe, true) Arrays.fill Arrays isSafe true for(int i=0;i<m;i++) {
			isSafe[sc.nextInt()]=false;
		} int i=0; int i=0; i 0 i<m i m i++ i++ i {
			isSafe[sc.nextInt()]=false;
		} {
			isSafe[sc.nextInt()]=false;
		} isSafe[sc.nextInt()]=false isSafe[sc.nextInt()] isSafe sc.nextInt() sc.nextInt sc false long dp[] = new long[n+1]; dp new long[n+1] n+1 n 1 Arrays.fill(dp, 0) Arrays.fill Arrays dp 0 dp[0]=1 dp[0] dp 0 1 dp[1]=1 dp[1] dp 1 1 if(!isSafe[1]) dp[1]=0; !isSafe[1] isSafe[1] isSafe 1 dp[1]=0 dp[1] dp 1 0 for(int i=2;i<n+1;i++) {
			if(!isSafe[i])continue;
			dp[i]=(dp[i-1]+dp[i-2])%1000000007;
					 
		} int i=2; int i=2; i 2 i<n+1 i n+1 n 1 i++ i++ i {
			if(!isSafe[i])continue;
			dp[i]=(dp[i-1]+dp[i-2])%1000000007;
					 
		} {
			if(!isSafe[i])continue;
			dp[i]=(dp[i-1]+dp[i-2])%1000000007;
					 
		} if(!isSafe[i])continue; !isSafe[i] isSafe[i] isSafe i continue; dp[i]=(dp[i-1]+dp[i-2])%1000000007 dp[i] dp i (dp[i-1]+dp[i-2])%1000000007 (dp[i-1]+dp[i-2]) dp[i-1] dp i-1 i 1 dp[i-2] dp i-2 i 2 1000000007 System.out.println(dp[n]) System.out.println System.out System System.out dp[n] dp n String args[] args public class Main {

	public static void main(String args[]) {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int m = sc.nextInt();
		
		boolean[] isSafe=new boolean[n+1];
		Arrays.fill(isSafe, true);
		
		for(int i=0;i<m;i++) {
			isSafe[sc.nextInt()]=false;
		}
		long dp[] = new long[n+1];
		Arrays.fill(dp, 0);
		dp[0]=1;
		dp[1]=1;
		if(!isSafe[1]) dp[1]=0;
		for(int i=2;i<n+1;i++) {
			if(!isSafe[i])continue;
			dp[i]=(dp[i-1]+dp[i-2])%1000000007;
					 
		}
		System.out.println(dp[n]);
	}
} public class Main {

	public static void main(String args[]) {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int m = sc.nextInt();
		
		boolean[] isSafe=new boolean[n+1];
		Arrays.fill(isSafe, true);
		
		for(int i=0;i<m;i++) {
			isSafe[sc.nextInt()]=false;
		}
		long dp[] = new long[n+1];
		Arrays.fill(dp, 0);
		dp[0]=1;
		dp[1]=1;
		if(!isSafe[1]) dp[1]=0;
		for(int i=2;i<n+1;i++) {
			if(!isSafe[i])continue;
			dp[i]=(dp[i-1]+dp[i-2])%1000000007;
					 
		}
		System.out.println(dp[n]);
	}
} Main
import java.util.*;

public class Main {

	public static void main(String args[]) {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int m = sc.nextInt();
		
		boolean[] isSafe=new boolean[n+1];
		Arrays.fill(isSafe, true);
		
		for(int i=0;i<m;i++) {
			isSafe[sc.nextInt()]=false;
		}
		long dp[] = new long[n+1];
		Arrays.fill(dp, 0);
		dp[0]=1;
		dp[1]=1;
		if(!isSafe[1]) dp[1]=0;
		for(int i=2;i<n+1;i++) {
			if(!isSafe[i])continue;
			dp[i]=(dp[i-1]+dp[i-2])%1000000007;
					 
		}
		System.out.println(dp[n]);
	}
}
