import java.util.Arrays;
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int m = sc.nextInt();

        long step[] = new long[n+1];
        Arrays.fill(step, -1);
        step[0] = 1;
        step[1] = 1;

        for(int i=0; i < m; i++){
            int a = sc.nextInt();
            step[a] = 0;
        }

        for(int i=2; i <= n; i++){
            if(step[i] == -1) {
                step[i] = (step[i - 1] + step[i - 2]) % 1000000007;
            }
        }
        System.out.println(step[n]);
    }
} import java.util.Arrays; Arrays java.util import java.util.Scanner; Scanner 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();

        long step[] = new long[n+1];
        Arrays.fill(step, -1);
        step[0] = 1;
        step[1] = 1;

        for(int i=0; i < m; i++){
            int a = sc.nextInt();
            step[a] = 0;
        }

        for(int i=2; i <= n; i++){
            if(step[i] == -1) {
                step[i] = (step[i - 1] + step[i - 2]) % 1000000007;
            }
        }
        System.out.println(step[n]);
    }
} Main public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int m = sc.nextInt();

        long step[] = new long[n+1];
        Arrays.fill(step, -1);
        step[0] = 1;
        step[1] = 1;

        for(int i=0; i < m; i++){
            int a = sc.nextInt();
            step[a] = 0;
        }

        for(int i=2; i <= n; i++){
            if(step[i] == -1) {
                step[i] = (step[i - 1] + step[i - 2]) % 1000000007;
            }
        }
        System.out.println(step[n]);
    } main {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int m = sc.nextInt();

        long step[] = new long[n+1];
        Arrays.fill(step, -1);
        step[0] = 1;
        step[1] = 1;

        for(int i=0; i < m; i++){
            int a = sc.nextInt();
            step[a] = 0;
        }

        for(int i=2; i <= n; i++){
            if(step[i] == -1) {
                step[i] = (step[i - 1] + step[i - 2]) % 1000000007;
            }
        }
        System.out.println(step[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 long step[] = new long[n+1]; step new long[n+1] n+1 n 1 Arrays.fill(step, -1) Arrays.fill Arrays step -1 1 step[0] = 1 step[0] step 0 1 step[1] = 1 step[1] step 1 1 for(int i=0; i < m; i++){
            int a = sc.nextInt();
            step[a] = 0;
        } int i=0; int i=0; i 0 i < m i m i++ i++ i {
            int a = sc.nextInt();
            step[a] = 0;
        } {
            int a = sc.nextInt();
            step[a] = 0;
        } int a = sc.nextInt(); a sc.nextInt() sc.nextInt sc step[a] = 0 step[a] step a 0 for(int i=2; i <= n; i++){
            if(step[i] == -1) {
                step[i] = (step[i - 1] + step[i - 2]) % 1000000007;
            }
        } int i=2; int i=2; i 2 i <= n i n i++ i++ i {
            if(step[i] == -1) {
                step[i] = (step[i - 1] + step[i - 2]) % 1000000007;
            }
        } {
            if(step[i] == -1) {
                step[i] = (step[i - 1] + step[i - 2]) % 1000000007;
            }
        } if(step[i] == -1) {
                step[i] = (step[i - 1] + step[i - 2]) % 1000000007;
            } step[i] == -1 step[i] step i -1 1 {
                step[i] = (step[i - 1] + step[i - 2]) % 1000000007;
            } step[i] = (step[i - 1] + step[i - 2]) % 1000000007 step[i] step i (step[i - 1] + step[i - 2]) % 1000000007 (step[i - 1] + step[i - 2]) step[i - 1] step i - 1 i 1 step[i - 2] step i - 2 i 2 1000000007 System.out.println(step[n]) System.out.println System.out System System.out step[n] step 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();

        long step[] = new long[n+1];
        Arrays.fill(step, -1);
        step[0] = 1;
        step[1] = 1;

        for(int i=0; i < m; i++){
            int a = sc.nextInt();
            step[a] = 0;
        }

        for(int i=2; i <= n; i++){
            if(step[i] == -1) {
                step[i] = (step[i - 1] + step[i - 2]) % 1000000007;
            }
        }
        System.out.println(step[n]);
    }
} public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int m = sc.nextInt();

        long step[] = new long[n+1];
        Arrays.fill(step, -1);
        step[0] = 1;
        step[1] = 1;

        for(int i=0; i < m; i++){
            int a = sc.nextInt();
            step[a] = 0;
        }

        for(int i=2; i <= n; i++){
            if(step[i] == -1) {
                step[i] = (step[i - 1] + step[i - 2]) % 1000000007;
            }
        }
        System.out.println(step[n]);
    }
} Main
import java.util.Arrays;
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int m = sc.nextInt();

        long step[] = new long[n+1];
        Arrays.fill(step, -1);
        step[0] = 1;
        step[1] = 1;

        for(int i=0; i < m; i++){
            int a = sc.nextInt();
            step[a] = 0;
        }

        for(int i=2; i <= n; i++){
            if(step[i] == -1) {
                step[i] = (step[i - 1] + step[i - 2]) % 1000000007;
            }
        }
        System.out.println(step[n]);
    }
}