The relationship between Albus Dumbledore and Gellert Grindelwald is a complex one that has been explored in the Harry Potter series. To answer the question of whether or not Dumbledore likes Grindelwald is difficult, as it is impossible to know the true thoughts and intentions of an individual.
At first glance, Dumbledore’s actions toward Grindelwald may appear to be those of a man who dislikes his adversary. He is quick to challenge Grindelwald to a duel when they meet after a long time apart, and even uses the Elder Wand against him in the battle. His behavior demonstrates that he is willing to take drastic and decisive actions in order to stop Grindelwald from achieving his goals.
However, there are moments in the series that suggest Dumbledore may have some degree of fondness toward Grindelwald. For example, when Dumbledore visits the grave of his sister, Ariana, he speaks of Grindelwald with a certain level of admiration, even though he had caused her death. He also seems to regret the fact that he had to fight his former friend and express a sense of loss for their relationship.
It is also worth noting that Dumbledore never took any action against Grindelwald until the wizard began to gain power and threaten the safety of others. It could be argued that he prolonged the fight in order to give Grindelwald a chance to change his ways and turn away from the dark path he had taken.
In the end, it is impossible to know for certain how Dumbledore felt about Grindelwald. While his actions may point to a dislike of the wizard, he never expressed any negative feelings towards him. His behavior may have even been motivated by a sense of grief and sorrow rather than hatred or disdain. Ultimately, while it is difficult to know the true thoughts of Albus Dumbledore, it appears that his relationship with Grindelwald was more complicated than just a simple dislike.