实现分组密码的CTR模式

def solve(____):
    blocks = blocks.split(____) if isinstance(____) else blocks
    result = []
    for i, block in enumerate(____):
        counter = f"____"
        keystream = '____'.join(chr(ord(____) ^ ord(key[j % len(____)])) for j, c in enumerate(____))
        encrypted = '____'.join(chr(ord(____) ^ ord(____)) for b, k in zip(____))
        result.append(____)
    print(____)