import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class Main {

	public static void main(String args[]) throws IOException {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

		String str[] = br.readLine().split(" ");
		int n = Integer.parseInt(str[0]);
		int m = Integer.parseInt(str[1]);

		int dp[] = new int[100010];

		for (int i = 0; i < m; i++) {
			int a = Integer.parseInt(br.readLine());
			dp[a] = Integer.MAX_VALUE;
		}

		dp[0] = 1;
		if (dp[1] == Integer.MAX_VALUE) {
			dp[1] = 0;
		} else {
			dp[1] = 1;
		}

		for (int i = 2; i <= n; i++) {
			if (dp[i] == Integer.MAX_VALUE) {
				dp[i] = 0;
			} else {
				dp[i] = dp[i - 1] % 1000000007 + dp[i - 2] % 1000000007;
			}
		}

		System.out.println(dp[n] % 1000000007);
	}
} import java.io.BufferedReader; BufferedReader java.io import java.io.IOException; IOException java.io import java.io.InputStreamReader; InputStreamReader java.io public class Main {

	public static void main(String args[]) throws IOException {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

		String str[] = br.readLine().split(" ");
		int n = Integer.parseInt(str[0]);
		int m = Integer.parseInt(str[1]);

		int dp[] = new int[100010];

		for (int i = 0; i < m; i++) {
			int a = Integer.parseInt(br.readLine());
			dp[a] = Integer.MAX_VALUE;
		}

		dp[0] = 1;
		if (dp[1] == Integer.MAX_VALUE) {
			dp[1] = 0;
		} else {
			dp[1] = 1;
		}

		for (int i = 2; i <= n; i++) {
			if (dp[i] == Integer.MAX_VALUE) {
				dp[i] = 0;
			} else {
				dp[i] = dp[i - 1] % 1000000007 + dp[i - 2] % 1000000007;
			}
		}

		System.out.println(dp[n] % 1000000007);
	}
} Main public static void main(String args[]) throws IOException {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

		String str[] = br.readLine().split(" ");
		int n = Integer.parseInt(str[0]);
		int m = Integer.parseInt(str[1]);

		int dp[] = new int[100010];

		for (int i = 0; i < m; i++) {
			int a = Integer.parseInt(br.readLine());
			dp[a] = Integer.MAX_VALUE;
		}

		dp[0] = 1;
		if (dp[1] == Integer.MAX_VALUE) {
			dp[1] = 0;
		} else {
			dp[1] = 1;
		}

		for (int i = 2; i <= n; i++) {
			if (dp[i] == Integer.MAX_VALUE) {
				dp[i] = 0;
			} else {
				dp[i] = dp[i - 1] % 1000000007 + dp[i - 2] % 1000000007;
			}
		}

		System.out.println(dp[n] % 1000000007);
	} main {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

		String str[] = br.readLine().split(" ");
		int n = Integer.parseInt(str[0]);
		int m = Integer.parseInt(str[1]);

		int dp[] = new int[100010];

		for (int i = 0; i < m; i++) {
			int a = Integer.parseInt(br.readLine());
			dp[a] = Integer.MAX_VALUE;
		}

		dp[0] = 1;
		if (dp[1] == Integer.MAX_VALUE) {
			dp[1] = 0;
		} else {
			dp[1] = 1;
		}

		for (int i = 2; i <= n; i++) {
			if (dp[i] == Integer.MAX_VALUE) {
				dp[i] = 0;
			} else {
				dp[i] = dp[i - 1] % 1000000007 + dp[i - 2] % 1000000007;
			}
		}

		System.out.println(dp[n] % 1000000007);
	} BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); br new BufferedReader(new InputStreamReader(System.in)) String str[] = br.readLine().split(" "); str br.readLine().split(" ") br.readLine().split br.readLine() br.readLine br " " int n = Integer.parseInt(str[0]); n Integer.parseInt(str[0]) Integer.parseInt Integer str[0] str 0 int m = Integer.parseInt(str[1]); m Integer.parseInt(str[1]) Integer.parseInt Integer str[1] str 1 int dp[] = new int[100010]; dp new int[100010] 100010 for (int i = 0; i < m; i++) {
			int a = Integer.parseInt(br.readLine());
			dp[a] = Integer.MAX_VALUE;
		} int i = 0; int i = 0; i 0 i < m i m i++ i++ i {
			int a = Integer.parseInt(br.readLine());
			dp[a] = Integer.MAX_VALUE;
		} {
			int a = Integer.parseInt(br.readLine());
			dp[a] = Integer.MAX_VALUE;
		} int a = Integer.parseInt(br.readLine()); a Integer.parseInt(br.readLine()) Integer.parseInt Integer br.readLine() br.readLine br dp[a] = Integer.MAX_VALUE dp[a] dp a Integer.MAX_VALUE Integer Integer.MAX_VALUE dp[0] = 1 dp[0] dp 0 1 if (dp[1] == Integer.MAX_VALUE) {
			dp[1] = 0;
		} else {
			dp[1] = 1;
		} dp[1] == Integer.MAX_VALUE dp[1] dp 1 Integer.MAX_VALUE Integer Integer.MAX_VALUE {
			dp[1] = 0;
		} dp[1] = 0 dp[1] dp 1 0 {
			dp[1] = 1;
		} dp[1] = 1 dp[1] dp 1 1 for (int i = 2; i <= n; i++) {
			if (dp[i] == Integer.MAX_VALUE) {
				dp[i] = 0;
			} else {
				dp[i] = dp[i - 1] % 1000000007 + dp[i - 2] % 1000000007;
			}
		} int i = 2; int i = 2; i 2 i <= n i n i++ i++ i {
			if (dp[i] == Integer.MAX_VALUE) {
				dp[i] = 0;
			} else {
				dp[i] = dp[i - 1] % 1000000007 + dp[i - 2] % 1000000007;
			}
		} {
			if (dp[i] == Integer.MAX_VALUE) {
				dp[i] = 0;
			} else {
				dp[i] = dp[i - 1] % 1000000007 + dp[i - 2] % 1000000007;
			}
		} if (dp[i] == Integer.MAX_VALUE) {
				dp[i] = 0;
			} else {
				dp[i] = dp[i - 1] % 1000000007 + dp[i - 2] % 1000000007;
			} dp[i] == Integer.MAX_VALUE dp[i] dp i Integer.MAX_VALUE Integer Integer.MAX_VALUE {
				dp[i] = 0;
			} dp[i] = 0 dp[i] dp i 0 {
				dp[i] = dp[i - 1] % 1000000007 + dp[i - 2] % 1000000007;
			} dp[i] = dp[i - 1] % 1000000007 + dp[i - 2] % 1000000007 dp[i] dp i dp[i - 1] % 1000000007 + dp[i - 2] % 1000000007 dp[i - 1] % 1000000007 dp[i - 1] dp i - 1 i 1 1000000007 dp[i - 2] % 1000000007 dp[i - 2] dp i - 2 i 2 1000000007 System.out.println(dp[n] % 1000000007) System.out.println System.out System System.out dp[n] % 1000000007 dp[n] dp n 1000000007 String args[] args public class Main {

	public static void main(String args[]) throws IOException {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

		String str[] = br.readLine().split(" ");
		int n = Integer.parseInt(str[0]);
		int m = Integer.parseInt(str[1]);

		int dp[] = new int[100010];

		for (int i = 0; i < m; i++) {
			int a = Integer.parseInt(br.readLine());
			dp[a] = Integer.MAX_VALUE;
		}

		dp[0] = 1;
		if (dp[1] == Integer.MAX_VALUE) {
			dp[1] = 0;
		} else {
			dp[1] = 1;
		}

		for (int i = 2; i <= n; i++) {
			if (dp[i] == Integer.MAX_VALUE) {
				dp[i] = 0;
			} else {
				dp[i] = dp[i - 1] % 1000000007 + dp[i - 2] % 1000000007;
			}
		}

		System.out.println(dp[n] % 1000000007);
	}
} public class Main {

	public static void main(String args[]) throws IOException {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

		String str[] = br.readLine().split(" ");
		int n = Integer.parseInt(str[0]);
		int m = Integer.parseInt(str[1]);

		int dp[] = new int[100010];

		for (int i = 0; i < m; i++) {
			int a = Integer.parseInt(br.readLine());
			dp[a] = Integer.MAX_VALUE;
		}

		dp[0] = 1;
		if (dp[1] == Integer.MAX_VALUE) {
			dp[1] = 0;
		} else {
			dp[1] = 1;
		}

		for (int i = 2; i <= n; i++) {
			if (dp[i] == Integer.MAX_VALUE) {
				dp[i] = 0;
			} else {
				dp[i] = dp[i - 1] % 1000000007 + dp[i - 2] % 1000000007;
			}
		}

		System.out.println(dp[n] % 1000000007);
	}
} Main
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class Main {

	public static void main(String args[]) throws IOException {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

		String str[] = br.readLine().split(" ");
		int n = Integer.parseInt(str[0]);
		int m = Integer.parseInt(str[1]);

		int dp[] = new int[100010];

		for (int i = 0; i < m; i++) {
			int a = Integer.parseInt(br.readLine());
			dp[a] = Integer.MAX_VALUE;
		}

		dp[0] = 1;
		if (dp[1] == Integer.MAX_VALUE) {
			dp[1] = 0;
		} else {
			dp[1] = 1;
		}

		for (int i = 2; i <= n; i++) {
			if (dp[i] == Integer.MAX_VALUE) {
				dp[i] = 0;
			} else {
				dp[i] = dp[i - 1] % 1000000007 + dp[i - 2] % 1000000007;
			}
		}

		System.out.println(dp[n] % 1000000007);
	}
}