Editing 3065 - trio (section)

== Rezolvare ==
<syntaxhighlight lang="python" line>
def reverse_piece(piece):
    """Returnează piesa inversată."""
    return piece[::-1]

def are_friends(piece1, piece2):
    """Verifică dacă două piese sunt prietene."""
    if piece1 == piece2:
        return True
    if piece1 == reverse_piece(piece2):
        return True
    c1, c2, c3 = piece1
    for i in range(3):
        if piece2 == c2 + c3 + c1 or piece2 == c3 + c1 + c2:
            return True
        c1, c2, c3 = c3, c1, c2  # permutăm cifrele
    return False

def cerinta1(pieces):
    """Determină M al pieselor identice cu cea selectată."""
    from collections import Counter
    counter = Counter(pieces)
    most_common_piece, count = counter.most_common(1)[0]
    return count

def cerinta2(pieces):
    """Numărul grupurilor de piese prietene."""
    n = len(pieces)
    visited = [False] * n

    def dfs(i):
        stack = [i]
        while stack:
            node = stack.pop()
            if not visited[node]:
                visited[node] = True
                for j in range(n):
                    if not visited[j] and are_friends(pieces[node], pieces[j]):
                        stack.append(j)

    groups = 0
    for i in range(n):
        if not visited[i]:
            groups += 1
            dfs(i)

    return groups

def cerinta3(pieces):
    """Numărul maxim de piese dintr-o secvență ce conține piese prietene."""
    n = len(pieces)
    max_length = 0
    current_length = 0

    for i in range(n):
        if i == 0 or are_friends(pieces[i], pieces[i - 1]):
            current_length += 1
        else:
            max_length = max(max_length, current_length)
            current_length = 1

    max_length = max(max_length, current_length)
    return max_length

def main():
    with open('trio.in', 'r') as f:
        data = f.read().splitlines()

    c = int(data[0].strip())
    n = int(data[1].strip())
    pieces = [line.strip().replace(" ", "") for line in data[2:2 + n]]

    assert 2 <= n <= 100000, "N trebuie să fie între 2 și 100000"
    assert all(len(piece) == 3 for piece in pieces), "Fiecare piesă trebuie să aibă exact 3 cifre"

    if c == 1:
        result = cerinta1(pieces)
    elif c == 2:
        result = cerinta2(pieces)
    elif c == 3:
        result = cerinta3(pieces)
    else:
        raise ValueError("C trebuie să fie 1, 2 sau 3")

    with open('trio.out', 'w') as f:
        f.write(f"{result}\n")

if __name__ == "__main__":
    main()

</syntaxhighlight>