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

import static java.lang.System.in;

public class Main {
    public static void main(String[] args) throws IOException {
        BufferedReader reader = new BufferedReader(new InputStreamReader(in));
        int N = Integer.parseInt(reader.readLine());
        int countRequired = 0;
        String l = reader.readLine();
        for (int i = 1; i < N; i++) {
            String s = reader.readLine();
            if (l.equals(s)) {
                countRequired += 1;
            } else {
                if (countRequired > 0) {
                    countRequired -= 1;
                }
                l = s;
            }
            System.out.println(countRequired + " , current " + l);
        }
        if(countRequired>0){
            System.out.println("NO");
        } else{
            System.out.println("YES");
        }
    }
}