dec n = 
    let a = n `div` 10
        b = n `mod` 10
    in
        b:(dec a)
dec n = 
    let a = n `div` 10
        b = n `mod` 10
    in
        b:(dec a)
dec n = 
    let a = n `div` 10
        b = n `mod` 10
    in
        b:(dec a)