The dotimes statement repeats its code a specified number of times. ( dotimes is a standard macro in Common Lisp.) Its format is:
(dotimes ( var n result ) code )
The variable var is bound inside the dotimes as if it appeared in a let. The value of var is set to 0 and the code is executed; then the value of var is incremented by 1 and the code is repeated, and so on. The total number of executions is n, so the last value of var is n - 1. If n is 0 or negative, the code is not executed.
(dotimes (i 5) (display i) (display " "))will write: 0 1 2 3 4 #f
The value of dotimes is result, which is optional; if there is no result, the value is #f.
; Iterative factorial (define (factorial n) (let ((product 1)) (dotimes (i n product) (set! product (* (1+ i) product)) ) ) )
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