import java.util.*;
import static java.lang.System.*;

public class Main{
  public static void main(String[] args){
	  Scanner sc = new Scanner(System.in);
	  
	  int N = sc.nextInt();
	  int M = sc.nextInt();
	  long [] DP = new long[N + 1]; //動的計画法

	  for(int i=0; i<M; i++) {
		  int n = sc.nextInt();
		  DP[n] = -1;
	  }
	  DP[0] = 1;
	  if(DP[1] != -1)DP[1] = 1;
	  else DP[1] = 0;
	  
	  for(int i=2; i<=N; i++) {
		  if ( DP[i] == -1) DP[i] = 0;
		  else {
			  DP[i] = DP[i-1] + DP[i-2];
			  DP[i] %= 1000000007;
		  }
	  }
	  long ans = DP[N] % 1000000007;
	  out.println(ans);
  }
} import java.util.*; util.* java import static java.lang.System.*; import static java.lang.System.*; import static java.lang.System.*; public class Main{
  public static void main(String[] args){
	  Scanner sc = new Scanner(System.in);
	  
	  int N = sc.nextInt();
	  int M = sc.nextInt();
	  long [] DP = new long[N + 1]; //動的計画法

	  for(int i=0; i<M; i++) {
		  int n = sc.nextInt();
		  DP[n] = -1;
	  }
	  DP[0] = 1;
	  if(DP[1] != -1)DP[1] = 1;
	  else DP[1] = 0;
	  
	  for(int i=2; i<=N; i++) {
		  if ( DP[i] == -1) DP[i] = 0;
		  else {
			  DP[i] = DP[i-1] + DP[i-2];
			  DP[i] %= 1000000007;
		  }
	  }
	  long ans = DP[N] % 1000000007;
	  out.println(ans);
  }
} Main public static void main(String[] args){
	  Scanner sc = new Scanner(System.in);
	  
	  int N = sc.nextInt();
	  int M = sc.nextInt();
	  long [] DP = new long[N + 1]; //動的計画法

	  for(int i=0; i<M; i++) {
		  int n = sc.nextInt();
		  DP[n] = -1;
	  }
	  DP[0] = 1;
	  if(DP[1] != -1)DP[1] = 1;
	  else DP[1] = 0;
	  
	  for(int i=2; i<=N; i++) {
		  if ( DP[i] == -1) DP[i] = 0;
		  else {
			  DP[i] = DP[i-1] + DP[i-2];
			  DP[i] %= 1000000007;
		  }
	  }
	  long ans = DP[N] % 1000000007;
	  out.println(ans);
  } main {
	  Scanner sc = new Scanner(System.in);
	  
	  int N = sc.nextInt();
	  int M = sc.nextInt();
	  long [] DP = new long[N + 1]; //動的計画法

	  for(int i=0; i<M; i++) {
		  int n = sc.nextInt();
		  DP[n] = -1;
	  }
	  DP[0] = 1;
	  if(DP[1] != -1)DP[1] = 1;
	  else DP[1] = 0;
	  
	  for(int i=2; i<=N; i++) {
		  if ( DP[i] == -1) DP[i] = 0;
		  else {
			  DP[i] = DP[i-1] + DP[i-2];
			  DP[i] %= 1000000007;
		  }
	  }
	  long ans = DP[N] % 1000000007;
	  out.println(ans);
  } 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 long [] DP = new long[N + 1]; DP new long[N + 1] N + 1 N 1 for(int i=0; i<M; i++) {
		  int n = sc.nextInt();
		  DP[n] = -1;
	  } int i=0; int i=0; i 0 i<M i M i++ i++ i {
		  int n = sc.nextInt();
		  DP[n] = -1;
	  } {
		  int n = sc.nextInt();
		  DP[n] = -1;
	  } int n = sc.nextInt(); n sc.nextInt() sc.nextInt sc DP[n] = -1 DP[n] DP n -1 1 DP[0] = 1 DP[0] DP 0 1 if(DP[1] != -1)DP[1] = 1;
	  else DP[1] = 0; DP[1] != -1 DP[1] DP 1 -1 1 DP[1] = 1 DP[1] DP 1 1 DP[1] = 0 DP[1] DP 1 0 for(int i=2; i<=N; i++) {
		  if ( DP[i] == -1) DP[i] = 0;
		  else {
			  DP[i] = DP[i-1] + DP[i-2];
			  DP[i] %= 1000000007;
		  }
	  } int i=2; int i=2; i 2 i<=N i N i++ i++ i {
		  if ( DP[i] == -1) DP[i] = 0;
		  else {
			  DP[i] = DP[i-1] + DP[i-2];
			  DP[i] %= 1000000007;
		  }
	  } {
		  if ( DP[i] == -1) DP[i] = 0;
		  else {
			  DP[i] = DP[i-1] + DP[i-2];
			  DP[i] %= 1000000007;
		  }
	  } if ( DP[i] == -1) DP[i] = 0;
		  else {
			  DP[i] = DP[i-1] + DP[i-2];
			  DP[i] %= 1000000007;
		  } DP[i] == -1 DP[i] DP i -1 1 DP[i] = 0 DP[i] DP i 0 {
			  DP[i] = DP[i-1] + DP[i-2];
			  DP[i] %= 1000000007;
		  } DP[i] = DP[i-1] + DP[i-2] DP[i] DP i DP[i-1] + DP[i-2] DP[i-1] DP i-1 i 1 DP[i-2] DP i-2 i 2 DP[i] %= 1000000007 DP[i] DP i 1000000007 long ans = DP[N] % 1000000007; ans DP[N] % 1000000007 DP[N] DP N 1000000007 out.println(ans) out.println out ans 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();
	  long [] DP = new long[N + 1]; //動的計画法

	  for(int i=0; i<M; i++) {
		  int n = sc.nextInt();
		  DP[n] = -1;
	  }
	  DP[0] = 1;
	  if(DP[1] != -1)DP[1] = 1;
	  else DP[1] = 0;
	  
	  for(int i=2; i<=N; i++) {
		  if ( DP[i] == -1) DP[i] = 0;
		  else {
			  DP[i] = DP[i-1] + DP[i-2];
			  DP[i] %= 1000000007;
		  }
	  }
	  long ans = DP[N] % 1000000007;
	  out.println(ans);
  }
} public class Main{
  public static void main(String[] args){
	  Scanner sc = new Scanner(System.in);
	  
	  int N = sc.nextInt();
	  int M = sc.nextInt();
	  long [] DP = new long[N + 1]; //動的計画法

	  for(int i=0; i<M; i++) {
		  int n = sc.nextInt();
		  DP[n] = -1;
	  }
	  DP[0] = 1;
	  if(DP[1] != -1)DP[1] = 1;
	  else DP[1] = 0;
	  
	  for(int i=2; i<=N; i++) {
		  if ( DP[i] == -1) DP[i] = 0;
		  else {
			  DP[i] = DP[i-1] + DP[i-2];
			  DP[i] %= 1000000007;
		  }
	  }
	  long ans = DP[N] % 1000000007;
	  out.println(ans);
  }
} Main
import java.util.*;
import static java.lang.System.*;

public class Main{
  public static void main(String[] args){
	  Scanner sc = new Scanner(System.in);
	  
	  int N = sc.nextInt();
	  int M = sc.nextInt();
	  long [] DP = new long[N + 1]; //動的計画法

	  for(int i=0; i<M; i++) {
		  int n = sc.nextInt();
		  DP[n] = -1;
	  }
	  DP[0] = 1;
	  if(DP[1] != -1)DP[1] = 1;
	  else DP[1] = 0;
	  
	  for(int i=2; i<=N; i++) {
		  if ( DP[i] == -1) DP[i] = 0;
		  else {
			  DP[i] = DP[i-1] + DP[i-2];
			  DP[i] %= 1000000007;
		  }
	  }
	  long ans = DP[N] % 1000000007;
	  out.println(ans);
  }
}