def get_distinct_country_stamp(N, countries):
    country_set = set()  
    for country in countries:  
        country_set.add(country)  
    return len(country_set)  
    
N = int(input().strip())
countries = [input().strip() for i in range(N)]

count = get_distinct_country_stamp(N, countries)
print(f"{count}")