You are a helpful assistant that can solve the given question step by step with the help of the wikipedia search tool and python interpreter tool. Given a question, you need to first think about the reasoning process in the mind and then provide the answer. During thinking, you can invoke the wikipedia search tool to search and python interpreter tool to calculate the math problem for fact information about specific topics if needed. The reasoning process and answer are enclosed within <think> </think> and <answer> </answer> tags respectively, and the search query and result are enclosed within <search> </search> and <result> </result> tags respectively. For example, <think> This is the reasoning process. </think> <search> search query here </search> <result> search result here </result> <think> This is the reasoning process. </think> <python> python code here </python> <result> python interpreter result here </result> <think> This is the reasoning process. </think> <answer> The final answer is \[ oxed{answer here} \] </answer>. In the last part of the answer, the final exact answer is enclosed within oxed{} with latex format.
system
Ivan Tsarevich is fighting the Dragon Gorynych on the Kalinov Bridge. The Dragon has 198 heads. With one swing of his sword, Ivan Tsarevich can cut off five heads. However, new heads immediately grow back, the number of which is equal to the remainder when the number of heads left after Ivan's swing is divided by 9. If the remaining number of heads is divisible by 9, no new heads grow. If the Dragon has five or fewer heads before the swing, Ivan Tsarevich can kill the Dragon with one swing. How many sword swings does Ivan Tsarevich need to defeat the Dragon Gorynych?
user
40
rule
Ivan Tsarevich is fighting the Dragon Gorynych on the Kalinov Bridge. The Dragon has 198 heads. With one swing of his sword, Ivan Tsarevich can cut off five heads. However, new heads immediately grow back, the number of which is equal to the remainder when the number of heads left after Ivan's swing is divided by 9. If the remaining number of heads is divisible by 9, no new heads grow. If the Dragon has five or fewer heads before the swing, Ivan Tsarevich can kill the Dragon with one swing. How many sword swings does Ivan Tsarevich need to defeat the Dragon Gorynych?
train