source_code: import java.util.*;
  import java.io.*;
  
  public class p3sol{
  
  	static char[] c;
  	static int[][] dp;
  	static int mod = (int)1e9 + 7;
  
  	public static void main(String[] args) throws Exception{
  		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
  		
  		int n = Integer.parseInt(br.readLine());
  		c = new char[n];
  
  		for(int i = 0; i < n; i++)
  			c[i] = br.readLine().charAt(0);
  
  		dp = new int[n + 1][n + 1];
  
  		dp[0][0] = 1;
  
  		for(int i = 0; i < n - 1; i++){
  			if(c[i] == 's'){
  				int prev = 0;
  				for(int j = i; j >= 0; j--){
  					prev += dp[i][j];
  					prev %= mod;
  					dp[i + 1][j] += prev;
  					dp[i + 1][j] %= mod;
  				}
  			}
  			else{
  				for(int j = 1; j <= n; j++){
  					dp[i + 1][j] += dp[i][j - 1];
  					dp[i + 1][j] %= mod;
  				}
  			}
  		}
  
  		int ans = 0;
  		for(int i = 0; i < n; i++){
  			ans += dp[n - 1][i];
  			ans %= mod;
  		}
  
  		// print(dp);
  
  		System.out.println(ans);
  		
  		br.close();
  	}
  
  	public static void print(int[][] a){
  		for(int i = 0; i < a.length; i++){
  			for(int j = 0; j < a[0].length; j++)
  				System.out.print(a[i][j] + " ");
  			System.out.println("");
  		}
  	}
  
  }