def count_unique_concatenated_strings(N, strings):
    unique_strings = set()
    for i in range(N):
        for j in range(i + 1, N):
            unique_strings.add(strings[i] + strings[j])
            unique_strings.add(strings[j] + strings[i])
    return len(unique_strings)
N = int(input())
inputs = [input() for _ in range(N)]
print(count_unique_concatenated_strings(N, inputs))