

import java.util.Scanner;

public class Main {
public static void main(String args[])
{
	Scanner scan=new Scanner(System.in);
	int n=scan.nextInt();
	int m=scan.nextInt();
	int ar[]=new int[m];
	int dp[]=new int[n+1];
	for(int i=0;i<m;i++)
	{
		dp[scan.nextInt()]=-1;
	}
	dp[0]=(dp[0]==0)?1:-1;
	dp[1]=(dp[1]==0)?1:-1;
	for(int i=2;i<=n;i++)
	{
		if(dp[i]==-1)continue;
		int x=(dp[i-1]==-1)?0:dp[i-1];
		int y=(dp[i-2]==-1)?0:dp[i-2];
		dp[i]=(x+y)%1000000007;
	}
	System.out.println(dp[n]);
}
} import java.util.Scanner; Scanner java.util public class Main {
public static void main(String args[])
{
	Scanner scan=new Scanner(System.in);
	int n=scan.nextInt();
	int m=scan.nextInt();
	int ar[]=new int[m];
	int dp[]=new int[n+1];
	for(int i=0;i<m;i++)
	{
		dp[scan.nextInt()]=-1;
	}
	dp[0]=(dp[0]==0)?1:-1;
	dp[1]=(dp[1]==0)?1:-1;
	for(int i=2;i<=n;i++)
	{
		if(dp[i]==-1)continue;
		int x=(dp[i-1]==-1)?0:dp[i-1];
		int y=(dp[i-2]==-1)?0:dp[i-2];
		dp[i]=(x+y)%1000000007;
	}
	System.out.println(dp[n]);
}
} Main public static void main(String args[])
{
	Scanner scan=new Scanner(System.in);
	int n=scan.nextInt();
	int m=scan.nextInt();
	int ar[]=new int[m];
	int dp[]=new int[n+1];
	for(int i=0;i<m;i++)
	{
		dp[scan.nextInt()]=-1;
	}
	dp[0]=(dp[0]==0)?1:-1;
	dp[1]=(dp[1]==0)?1:-1;
	for(int i=2;i<=n;i++)
	{
		if(dp[i]==-1)continue;
		int x=(dp[i-1]==-1)?0:dp[i-1];
		int y=(dp[i-2]==-1)?0:dp[i-2];
		dp[i]=(x+y)%1000000007;
	}
	System.out.println(dp[n]);
} main {
	Scanner scan=new Scanner(System.in);
	int n=scan.nextInt();
	int m=scan.nextInt();
	int ar[]=new int[m];
	int dp[]=new int[n+1];
	for(int i=0;i<m;i++)
	{
		dp[scan.nextInt()]=-1;
	}
	dp[0]=(dp[0]==0)?1:-1;
	dp[1]=(dp[1]==0)?1:-1;
	for(int i=2;i<=n;i++)
	{
		if(dp[i]==-1)continue;
		int x=(dp[i-1]==-1)?0:dp[i-1];
		int y=(dp[i-2]==-1)?0:dp[i-2];
		dp[i]=(x+y)%1000000007;
	}
	System.out.println(dp[n]);
} Scanner scan=new Scanner(System.in); scan new Scanner(System.in) int n=scan.nextInt(); n scan.nextInt() scan.nextInt scan int m=scan.nextInt(); m scan.nextInt() scan.nextInt scan int ar[]=new int[m]; ar new int[m] m int dp[]=new int[n+1]; dp new int[n+1] n+1 n 1 for(int i=0;i<m;i++)
	{
		dp[scan.nextInt()]=-1;
	} int i=0; int i=0; i 0 i<m i m i++ i++ i {
		dp[scan.nextInt()]=-1;
	} {
		dp[scan.nextInt()]=-1;
	} dp[scan.nextInt()]=-1 dp[scan.nextInt()] dp scan.nextInt() scan.nextInt scan -1 1 dp[0]=(dp[0]==0)?1:-1 dp[0] dp 0 (dp[0]==0)?1:-1 (dp[0]==0) dp[0] dp 0 0 1 -1 1 dp[1]=(dp[1]==0)?1:-1 dp[1] dp 1 (dp[1]==0)?1:-1 (dp[1]==0) dp[1] dp 1 0 1 -1 1 for(int i=2;i<=n;i++)
	{
		if(dp[i]==-1)continue;
		int x=(dp[i-1]==-1)?0:dp[i-1];
		int y=(dp[i-2]==-1)?0:dp[i-2];
		dp[i]=(x+y)%1000000007;
	} int i=2; int i=2; i 2 i<=n i n i++ i++ i {
		if(dp[i]==-1)continue;
		int x=(dp[i-1]==-1)?0:dp[i-1];
		int y=(dp[i-2]==-1)?0:dp[i-2];
		dp[i]=(x+y)%1000000007;
	} {
		if(dp[i]==-1)continue;
		int x=(dp[i-1]==-1)?0:dp[i-1];
		int y=(dp[i-2]==-1)?0:dp[i-2];
		dp[i]=(x+y)%1000000007;
	} if(dp[i]==-1)continue; dp[i]==-1 dp[i] dp i -1 1 continue; int x=(dp[i-1]==-1)?0:dp[i-1]; x (dp[i-1]==-1)?0:dp[i-1] (dp[i-1]==-1) dp[i-1] dp i-1 i 1 -1 1 0 dp[i-1] dp i-1 i 1 int y=(dp[i-2]==-1)?0:dp[i-2]; y (dp[i-2]==-1)?0:dp[i-2] (dp[i-2]==-1) dp[i-2] dp i-2 i 2 -1 1 0 dp[i-2] dp i-2 i 2 dp[i]=(x+y)%1000000007 dp[i] dp i (x+y)%1000000007 (x+y) x y 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 scan=new Scanner(System.in);
	int n=scan.nextInt();
	int m=scan.nextInt();
	int ar[]=new int[m];
	int dp[]=new int[n+1];
	for(int i=0;i<m;i++)
	{
		dp[scan.nextInt()]=-1;
	}
	dp[0]=(dp[0]==0)?1:-1;
	dp[1]=(dp[1]==0)?1:-1;
	for(int i=2;i<=n;i++)
	{
		if(dp[i]==-1)continue;
		int x=(dp[i-1]==-1)?0:dp[i-1];
		int y=(dp[i-2]==-1)?0:dp[i-2];
		dp[i]=(x+y)%1000000007;
	}
	System.out.println(dp[n]);
}
} public class Main {
public static void main(String args[])
{
	Scanner scan=new Scanner(System.in);
	int n=scan.nextInt();
	int m=scan.nextInt();
	int ar[]=new int[m];
	int dp[]=new int[n+1];
	for(int i=0;i<m;i++)
	{
		dp[scan.nextInt()]=-1;
	}
	dp[0]=(dp[0]==0)?1:-1;
	dp[1]=(dp[1]==0)?1:-1;
	for(int i=2;i<=n;i++)
	{
		if(dp[i]==-1)continue;
		int x=(dp[i-1]==-1)?0:dp[i-1];
		int y=(dp[i-2]==-1)?0:dp[i-2];
		dp[i]=(x+y)%1000000007;
	}
	System.out.println(dp[n]);
}
} Main


import java.util.Scanner;

public class Main {
public static void main(String args[])
{
	Scanner scan=new Scanner(System.in);
	int n=scan.nextInt();
	int m=scan.nextInt();
	int ar[]=new int[m];
	int dp[]=new int[n+1];
	for(int i=0;i<m;i++)
	{
		dp[scan.nextInt()]=-1;
	}
	dp[0]=(dp[0]==0)?1:-1;
	dp[1]=(dp[1]==0)?1:-1;
	for(int i=2;i<=n;i++)
	{
		if(dp[i]==-1)continue;
		int x=(dp[i-1]==-1)?0:dp[i-1];
		int y=(dp[i-2]==-1)?0:dp[i-2];
		dp[i]=(x+y)%1000000007;
	}
	System.out.println(dp[n]);
}
}
