小编Rom*_*kov的帖子

任何人都可以帮忙解决这个问题吗？

编写一个程序,询问用户直角三角形的底边和高度,计算其面积并将其打印到屏幕上.交互应该类似于:

The base?
3.3
The height?
5.4
The area of that triangle is 8.91

解决:

getTriArea :: IO Float
getTriArea = do
 putStr "The base? "
 base <- getLine
 putStr "The height? "
 height <- getLine
 let ar = ( (read base :: Float) * (read height :: Float) )/ 2
 return ar

main = do 
 result <- getTriArea
 putStr $ "The area of that triangle is " ++ show result