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

public class Solution {
	public static final long MOD = (long)1e9 + 7L;

    public static int nSize = 0;
    public static long[] memo = new long[300001];

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

		int n = Integer.parseInt(br.readLine().trim());
		String s = br.readLine().trim();
		// compute and print answer here

        for(int i = n-1; i >= 0; i--){
            if(i == n-1){
                memo[i] = 1;
            }
            else if(i == n-2 && s.charAt(i) == '0'){
                memo[i] = 1;
            }
            else if(i == n-3 && s.charAt(i) == '0'){
                memo[i] = 2;
            }
            else{
                if( (i+2 < n && i+1 < n)      &&
                    (s.charAt(i+2) == '0' && s.charAt(i+1) == '0')){
                    memo[i] = memo[i+2] + memo[i+1];
                }
                else if(i+2 < n && s.charAt(i+2) == '0'){
                    memo[i] = memo[i+2];
                }
                else if(i+1 < n && s.charAt(i+1) == '0'){
                    memo[i] = memo[i+1];
                }
            }
        }


        System.out.println(memo[0]);

	}
}