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Ala ud din Khilji's military ambitions required a standing and strong army, especially after the Mongol siege of Delhi. Maintaining a large army at regular salaries, however, would be severe drain on the treasury. A system of price controls reduced the salary amount that needed to be paid. Three separate markets were set up in Delhi. The first one for food grains, the second for cloth and items such as ghee, oil and sugar. The third market was horses, cattle, and slaves. Regulations were laid out for the operations of these markets. He took various steps to control the prices. He exercised supervisions over the market. He fixed the prices of all the commodities from top to bottom. Market officers called shahna were appointed to keep a check on the prices. The defaulters were heavily punished. Land revenue was fixed and the grain was stored in government granaries. These market regulations and stability of prices were the wonders of his age. The soldiers and the civil population were greatly benefitted from these measures due to the low prices of the essential goods.