In Racket, it's that simple using Iterations and Comprehensions :
(for* ([i (in-range numb1)] [j (in-range numb2)]) <body of iteration>)
The above will only work on Racket. For comparison, the following snippets will work in any standard RxRS interpreter - for example, using a pair of nested do :
(do ((i 0 (+ i 1))) ((= i numb1)) (do ((j 0 (+ j 1))) ((= j numb2)) <body of iteration>))
Another option: using explicit recursion and the name let :
(let loop1 ((i 0)) (cond ((< i numb1) (let loop2 ((j 0)) (cond ((< j numb2) <body of iteration> (loop2 (+ j 1))))) (loop1 (+ i 1)))))
Finally, you can always do something like the following: SICP in the Nested Mappings section for details:
(define (range start stop) (let loop ((i (- stop 1)) (acc '())) (if (< i start) acc (loop (- i 1) (cons i acc))))) (for-each (lambda (i) (for-each (lambda (j) <body of iteration>) (range 0 numb2))) (range 0 numb1))