(define randomly-fill! (lambda (v) (let ((size (vector-length v))) (define loop (lambda (loc) (cond ((= loc size)) (else (vector-set! v loc (+ 1 (random 100))) (loop (+ loc 1)))))) (loop 0)))) (define v (make-vector 10)) v ⇒ #(0 0 0 0 0 0 0 0 0 0) (randomly-fill! v) v ⇒ #(85 94 83 6 10 31 45 19 41 56)