Instructions: In this task, you're given a passage, further information available on a particular linked term from the statement, and a question. Your job is to generate the answer to the question by using the information provided. If there is no clear answer obtainable, output 'none'.
Input: Passage: Relations between the people of Afghanistan and India traces to the Indus Valley Civilisation. Following Alexander the Great's brief occupation, the successor state of the Seleucid Empire controlled the region known today as Afghanistan. In 305 BCE, they ceded much of it to the Indian Maurya Empire as part of an alliance treaty. The Mauryans brought Buddhism from India and controlled the area south of the Hindu Kush. Their decline began 60 years after Ashoka's rule ended, leading to the Hellenistic reconquest of the region by the Greco-Bactrians. Much of it soon broke away from the Greco-Bactrians and became part of the Indo-Greek Kingdom. The Indo-Greeks had been defeated and expelled by the Indo-Scythians in the late 2nd century BCE. Much of Afghanistan has been influenced by Buddhist, Hindu and Zoroastrian cultures until the arrival of Islam in the 7th century. But despite many Afghans converting to Islam, the Muslims and Hindus lived side by side.
Link Information: According to the Sri Lankan texts Mahavamsa and the Dipavamsa, Ashoka ascended the throne 218 years after the death of Gautama Buddha, and ruled for 37 years. Question: How many years did the Ashoka's rule?
Output:
Answer: 37