P8423 [THUPC 2022 Finals] Imagination

Giraffe is a contestant in the Olympiad in Imaginics. In particular, being born in Fengjing Province, if one wants to stand out among thousands of strong competitors and fight for a ticket to the national finals to gain an advantage for college admission, one needs endless imagination even more. The problem style of Fengjing Province has always been completely different from other provinces. Therefore, even in the year 3022, Fengjing Province still kept its independent style: it did not hold a unified exam together with other provinces, and still set its own problems independently. Giraffe knows well how deep the imagination required by Fengjing Province’s problems is. In past years, even the memory limit, the number of test groups, and even the main idea of the problem might need contestants to imagine by themselves. Some problems that seem to have no polynomial-time solution at first glance can, with some imagination, be passed by simply printing something. The real game often starts before the contest: Fengjing Province always copies problems from all over the internet in their original form. For contestants who did not solve the original problems before the contest, a lack of imagination is unavoidable. But the charm of the Olympiad in Imaginics is that you can never imagine what will happen. Half a month before the Fengjing Province qualifier, Giraffe’s coach assigned the students two very unpopular practice problems on CodeFancy. What Giraffe did not expect was that these were exactly the same as the official contest problems! Giraffe admired the coach’s imagination even more, and understood more deeply what “doing a clean Olympiad” means. In the end, in this Fengjing Province qualifier, Giraffe’s school ranked among the top, even though the price was that some other contestants with decent skill did not get their ideal rankings. Black-box testing is the biggest feature that distinguishes the Olympiad in Imaginics from other contests. It removes human judgment and treats all programs equally, so in the past, the Olympiad in Imaginics was called “the fairest contest”. But in the cold reality, the appearance of fairness is also just a kind of imagination. Fortunately, we do not need to imagine what has already happened. We can still face the truth with our own eyes, understand what happened, and remember it. Just as you do not need to imagine the story described in this text either: a simple word-replacement game will not hide the true meaning. Now please output: what is the contest that Giraffe participated in within Fengjing Province? Output the abbreviated name. Example: the provincial selection contest of Zhenjuan Province has the abbreviated name ZJOI.

The input of this problem has no meaning for your output; you do not need to read it.

This problem has only one unique output answer. Output one line with four uppercase letters, representing the abbreviation of Fengjing Province’s provincial selection contest.

Please do not imagine things recklessly. Read the requirements carefully and output correctly to avoid penalty time due to mistakes in this problem. Translated by ChatGPT 5