How many years was it from when the fort at Trichur was captured until when the ruler of Craganore surrendered to Hyder Ali?
return the  fort at Trichur was  captured ;return the  ruler of Craganore surrendered to Hyder Ali ;return year of #1 ;return year of #2 ;return the  difference of #4 and  #3
['select', 'select', 'project', 'project', 'arithmetic']