Dolist Construct in LISP

DoList in Common LISP is a looping statement used to iterate the elements in a list.

Syntax:

(dolist input_list)
 statements...
)

Here,

• The input_list contains the list of elements that are iterated.
• The statements are present in the loop.

Example 1: LISP Program to iterate the list of elements from 1 to 5.

Lisp

;create a dolist of 1 to 5 elements in  a list
(dolist (n '(1 2 3 4 5 ))

;iterate elements
   (format t "~% List of elements: ~d " n)
)

Output:

List of elements: 1  
List of elements: 2  
List of elements: 3  
List of elements: 4  
List of elements: 5 

Example 2: LISP Program to find the square of each element by iteration.

Lisp

;create a dolist of 1 to 5 elements in  a list
(dolist (n '(1 2 3 4 5 ))

  ;iterate elements to print each element
  (format t "~% Element's value: ~d " n)

  ;iterate elements to find square of each element
  (format t "~% Square of element: ~d " (* n n))
  (terpri)
)

Output:

 Element's value: 1 
 Square of element: 1 

 Element's value: 2 
 Square of element: 4 

 Element's value: 3 
 Square of element: 9 

 Element's value: 4 
 Square of element: 16 

 Element's value: 5 
 Square of element: 25