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diff --git a/coding-exercises/2/62.rkt b/coding-exercises/2/62.rkt
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+++ b/coding-exercises/2/62.rkt
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+#lang racket
+
+;; In each branch of the problem we either terminate the process or we reduce the problem to a subproblem with set - (car set)
+(define (union-set set1 set2)
+  (cond ((and (null? set1) (null? set2)) '())
+        ((null? set1) (cons (car set2) (union-set set1 (cdr set2))))
+        ((null? set2) (cons (car set1) (union-set (cdr set1) set2)))
+        ((= (car set1) (car set2)) (cons (car set2) (union-set (cdr set1) (cdr set2))))
+        ((> (car set1) (car set2)) (cons (car set2) (union-set set1 (cdr set2))))
+        ((< (car set1) (car set2)) (cons (car set1) (union-set (cdr set1) set2)))))
+
+(define test-list (list 1 2))
+(define test-list2 (list 4 5 6 7))
+(union-set test-list test-list2)
+