(defun leap-year-p (year)
  "Check if a given year is a leap year."
  (or (and (zerop (mod year 4))        ; Check if the year is divisible by 4
           (not (zerop (mod year 100)))) ; Ensure it's not divisible by 100, except...
      (zerop (mod year 400))))          ; ...if it's also divisible by 400, then it's a leap year

(defun leapYear ()
  "Generate a list of leap years between 1800 and 2021."
  (loop for year from 1800 to 2021    ; Loop through the years from 1800 to 2021
        when (leap-year-p year)      ; Check if the current year is a leap year
        collect year))               ; If it is, collect it into a list

;; Call the function to get the list of leap years
(let ((leap-years (leapYear)))       ; Store the list of leap years in the variable leap-years
  (format t " ~a~%" leap-years)) ; Print the list of leap years

Common Lisp online compiler

Write, Run & Share Common Lisp code online using OneCompiler's Common Lisp online compiler for free. It's one of the robust, feature-rich online compilers for Common Lisp language, running the latest Common Lisp version 5.3. Getting started with the OneCompiler's Common Lisp editor is easy and fast. The editor shows sample boilerplate code when you choose language as Common Lisp and start coding.

Read inputs from stdin

OneCompiler's Common Lisp online editor supports stdin and users can give inputs to programs using the STDIN textbox under the I/O tab. Following is a sample Common Lisp program which takes name as input and prints hello message with your name.

(setq name (read))
(princ "Hello ")
(write name)

About Common Lisp

Common Lisp is a generic language suitable for a wide range of industry applications. It is often referred as Programmable programming language because of it's high extensibility, machine independence, extensive control structures, dynamic updation of programs etc.

Common LISP was invented by John McCarthy in 1958 and was first implemenyted by Steve Russell on an IBM 704 computer.

Syntax help

Variables

  • Global variables are declared using defvar keyword and these variables will be in effect until a new value is assigned.
  • Type declaration is not required in LISP

Example

(defvar x 10)
(write x)
  • Local variables are declared with in a function or a procedure. The scope of local variables will be only in that function.
  • let and progare used to declare local variables.

Syntax

(let ((var1  value1) (var2  value2).. (varn  valuen))<expressions>)
  • You can also create global and local variables using setq

Example

(setq a 10)

Loops

1. Loop:

This is the simplest looping mechanism in LISP. This allows the execute the set of statements repeatedly until a return statement is encountered.

Syntax

(loop (s-expressions))

2. For:

For loop is used to iterate a set of statements based on a condition.

(loop for loop-variable in <a list>
   do (action)
)

3. Do:

Do is also used to iterate a set of statements and then check the condition

(do ((var1    val1   updated-val1)
      (var2   val2   updated-val2)
      (var3   val3   updated-val3)
   ...)
   (test return-value)
   (s-expressions)
)

4. Dotimes:

Dotimes is used to iterate for fixed number of iterations.

Syntax:

(dotimes (n val)
  statements