import java.util.*;

public class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);       
		int n = Integer.parseInt(sc.next());
		int m = Integer.parseInt(sc.next());
		int[] a = new int[m];
		int[] b = new int[n+1];
		for(int i=0; i<m; i++) {
		    a[i] = Integer.parseInt(sc.next());
		    b[a[i]] = 1;
		}
		int[] dp = new int[n+1];
		dp[0] = 1;
		if(b[1] == 1) dp[1] = 0;
		else dp[1] = 1;
		if(n > 1) {
		    for(int i=2; i<n+1; i++) {
		        if(b[i] == 1) dp[i] = 0;
		        else dp[i] = (dp[i-1]+dp[i-2]) % 1000000007;
		    }
		}else {
		    dp[1] = 1;
		}
		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 = Integer.parseInt(sc.next());
		int m = Integer.parseInt(sc.next());
		int[] a = new int[m];
		int[] b = new int[n+1];
		for(int i=0; i<m; i++) {
		    a[i] = Integer.parseInt(sc.next());
		    b[a[i]] = 1;
		}
		int[] dp = new int[n+1];
		dp[0] = 1;
		if(b[1] == 1) dp[1] = 0;
		else dp[1] = 1;
		if(n > 1) {
		    for(int i=2; i<n+1; i++) {
		        if(b[i] == 1) dp[i] = 0;
		        else dp[i] = (dp[i-1]+dp[i-2]) % 1000000007;
		    }
		}else {
		    dp[1] = 1;
		}
		System.out.println(dp[n]);
	}
} Main public static void main(String[] args){
		Scanner sc = new Scanner(System.in);       
		int n = Integer.parseInt(sc.next());
		int m = Integer.parseInt(sc.next());
		int[] a = new int[m];
		int[] b = new int[n+1];
		for(int i=0; i<m; i++) {
		    a[i] = Integer.parseInt(sc.next());
		    b[a[i]] = 1;
		}
		int[] dp = new int[n+1];
		dp[0] = 1;
		if(b[1] == 1) dp[1] = 0;
		else dp[1] = 1;
		if(n > 1) {
		    for(int i=2; i<n+1; i++) {
		        if(b[i] == 1) dp[i] = 0;
		        else dp[i] = (dp[i-1]+dp[i-2]) % 1000000007;
		    }
		}else {
		    dp[1] = 1;
		}
		System.out.println(dp[n]);
	} main {
		Scanner sc = new Scanner(System.in);       
		int n = Integer.parseInt(sc.next());
		int m = Integer.parseInt(sc.next());
		int[] a = new int[m];
		int[] b = new int[n+1];
		for(int i=0; i<m; i++) {
		    a[i] = Integer.parseInt(sc.next());
		    b[a[i]] = 1;
		}
		int[] dp = new int[n+1];
		dp[0] = 1;
		if(b[1] == 1) dp[1] = 0;
		else dp[1] = 1;
		if(n > 1) {
		    for(int i=2; i<n+1; i++) {
		        if(b[i] == 1) dp[i] = 0;
		        else dp[i] = (dp[i-1]+dp[i-2]) % 1000000007;
		    }
		}else {
		    dp[1] = 1;
		}
		System.out.println(dp[n]);
	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int n = Integer.parseInt(sc.next()); n Integer.parseInt(sc.next()) Integer.parseInt Integer sc.next() sc.next sc int m = Integer.parseInt(sc.next()); m Integer.parseInt(sc.next()) Integer.parseInt Integer sc.next() sc.next sc int[] a = new int[m]; a new int[m] m int[] b = new int[n+1]; b new int[n+1] n+1 n 1 for(int i=0; i<m; i++) {
		    a[i] = Integer.parseInt(sc.next());
		    b[a[i]] = 1;
		} int i=0; int i=0; i 0 i<m i m i++ i++ i {
		    a[i] = Integer.parseInt(sc.next());
		    b[a[i]] = 1;
		} {
		    a[i] = Integer.parseInt(sc.next());
		    b[a[i]] = 1;
		} a[i] = Integer.parseInt(sc.next()) a[i] a i Integer.parseInt(sc.next()) Integer.parseInt Integer sc.next() sc.next sc b[a[i]] = 1 b[a[i]] b a[i] a i 1 int[] dp = new int[n+1]; dp new int[n+1] n+1 n 1 dp[0] = 1 dp[0] dp 0 1 if(b[1] == 1) dp[1] = 0;
		else dp[1] = 1; b[1] == 1 b[1] b 1 1 dp[1] = 0 dp[1] dp 1 0 dp[1] = 1 dp[1] dp 1 1 if(n > 1) {
		    for(int i=2; i<n+1; i++) {
		        if(b[i] == 1) dp[i] = 0;
		        else dp[i] = (dp[i-1]+dp[i-2]) % 1000000007;
		    }
		}else {
		    dp[1] = 1;
		} n > 1 n 1 {
		    for(int i=2; i<n+1; i++) {
		        if(b[i] == 1) dp[i] = 0;
		        else dp[i] = (dp[i-1]+dp[i-2]) % 1000000007;
		    }
		} for(int i=2; i<n+1; i++) {
		        if(b[i] == 1) dp[i] = 0;
		        else 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(b[i] == 1) dp[i] = 0;
		        else dp[i] = (dp[i-1]+dp[i-2]) % 1000000007;
		    } {
		        if(b[i] == 1) dp[i] = 0;
		        else dp[i] = (dp[i-1]+dp[i-2]) % 1000000007;
		    } if(b[i] == 1) dp[i] = 0;
		        else dp[i] = (dp[i-1]+dp[i-2]) % 1000000007; b[i] == 1 b[i] b i 1 dp[i] = 0 dp[i] dp i 0 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 {
		    dp[1] = 1;
		} dp[1] = 1 dp[1] dp 1 1 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 = Integer.parseInt(sc.next());
		int m = Integer.parseInt(sc.next());
		int[] a = new int[m];
		int[] b = new int[n+1];
		for(int i=0; i<m; i++) {
		    a[i] = Integer.parseInt(sc.next());
		    b[a[i]] = 1;
		}
		int[] dp = new int[n+1];
		dp[0] = 1;
		if(b[1] == 1) dp[1] = 0;
		else dp[1] = 1;
		if(n > 1) {
		    for(int i=2; i<n+1; i++) {
		        if(b[i] == 1) dp[i] = 0;
		        else dp[i] = (dp[i-1]+dp[i-2]) % 1000000007;
		    }
		}else {
		    dp[1] = 1;
		}
		System.out.println(dp[n]);
	}
} public class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);       
		int n = Integer.parseInt(sc.next());
		int m = Integer.parseInt(sc.next());
		int[] a = new int[m];
		int[] b = new int[n+1];
		for(int i=0; i<m; i++) {
		    a[i] = Integer.parseInt(sc.next());
		    b[a[i]] = 1;
		}
		int[] dp = new int[n+1];
		dp[0] = 1;
		if(b[1] == 1) dp[1] = 0;
		else dp[1] = 1;
		if(n > 1) {
		    for(int i=2; i<n+1; i++) {
		        if(b[i] == 1) dp[i] = 0;
		        else dp[i] = (dp[i-1]+dp[i-2]) % 1000000007;
		    }
		}else {
		    dp[1] = 1;
		}
		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 = Integer.parseInt(sc.next());
		int m = Integer.parseInt(sc.next());
		int[] a = new int[m];
		int[] b = new int[n+1];
		for(int i=0; i<m; i++) {
		    a[i] = Integer.parseInt(sc.next());
		    b[a[i]] = 1;
		}
		int[] dp = new int[n+1];
		dp[0] = 1;
		if(b[1] == 1) dp[1] = 0;
		else dp[1] = 1;
		if(n > 1) {
		    for(int i=2; i<n+1; i++) {
		        if(b[i] == 1) dp[i] = 0;
		        else dp[i] = (dp[i-1]+dp[i-2]) % 1000000007;
		    }
		}else {
		    dp[1] = 1;
		}
		System.out.println(dp[n]);
	}
}