You will be given a definition of a task first, then some input of the task.
This task involves creating answers to complex questions, from a given passage. Answering these questions, typically involve understanding multiple sentences. Make sure that your answer has the same type as the "answer type" mentioned in input. The provided "answer type" can be of any of the following types: "span", "date", "number". A "span" answer is a continuous phrase taken directly from the passage or question. You can directly copy-paste the text from the passage or the question for span type answers. If you find multiple spans, please add them all as a comma separated list. Please restrict each span to five words. A "number" type answer can include a digit specifying an actual value. For "date" type answers, use DD MM YYYY format e.g. 11 Jan 1992. If full date is not available in the passage you can write partial date such as 1992 or Jan 1992. If you find multiple spans, please add them all as a comma separated list. Please restrict each span to five words.

Passage: The Burmese too had begun to assemble their invasion force, starting during their new year celebrations in April 1759, gathering troops from all over Upper Burma, including from recently conquered northern Shan States and Manipur. By late 1759, Alaungpaya had massed a force of 40 regiments at Yangon. Of the 3000 cavalry, 2000 were Manipuri "Cassay Horse", who had just been press-ganged into Alaungpaya's service after the Burmese conquest of Manipur in 1758. The Burmese battle plan was to go around the heavily defended Siamese positions along the Three Pagodas Pass-Ayutthaya corridor. They selected a longer but less defended route: Go south to Tenasserim, cross the Tenasserim Hills over to Gulf of Siam, and turn north to Ayutthaya. To that end, the Burmese had assembled a fleet of 300 ships to transport a portion of their troops directly to the Tenasserim coast. Alaungpaya was to lead the invasion personally, and his second son Hsinbyushin was his second-in-command. His first son Naungdawgyi was left to administer the country. Also in his service were his top generals including the likes of Minkhaung Nawrahta who like all Burmese leadership had plenty of military experience. Some in the court urged him to stay behind and allow Hsinbyushin to lead the operation but the king refused.
Question: How many years after their conquest were the Manipuri "Cassay Horse" forced into Alaungpaya's service?
Answer type: Number
Output:
1.