package me.yukicoder.lv1;
import java.util.HashMap;
import java.util.Map;
import java.util.Scanner;

public class No0182 {
	public static void main(String[] args) {
		try (Scanner sc = new Scanner(System.in)) {
			int N = sc.nextInt();
			Map<String, Integer> m = new HashMap<>();

			for (int i = 0; i < N; i++) {
				String tmp = sc.next();
				m.putIfAbsent(tmp, 1);
				m.computeIfPresent(tmp, (k, v) -> (m.get(tmp) + 1));
			}
			long size = m.entrySet().stream().filter(map -> map.getValue().equals(1))
					.map(map -> map.getKey()).count();
			System.out.println(size);
		}
	}
}