+(define (unionE L1 L2)
+ (cond
+ ((null? L1) L2)
+ ((member (first L1) L2) (unionE (rest L1) L2))
+ ((cons (first L1) (unionE (rest L1) L2)))))
+(println "unionE/union")
+(println (unionE L M))
+(println (unionE N L))
+(println (union N L))
+
+;(trace true)
+
+(setq T '(((4)((2 5))((((((6 7)))))))))
+(define (prof L)
+ (cond
+ ((null? L) 0)
+ ((atom? L) 0)
+ ((max (+ 1 (prof (first L))) (prof (rest L))))))
+(println "prof")
+(println (prof L))
+(println (prof T))
+
+;(trace nil)
+;(trace true)
+
+(define (aplatir L)
+ (cond
+ ((null? L) '())
+ ((atom? L) (list L))
+ ((append (aplatir (first L)) (aplatir (rest L))))))
+(println "aplatir/flat")
+(println (aplatir T))
+(println (flat T))
+
+;(trace nil)
+
+(define (elim L)
+ (cond
+ ((null? L) '())
+ ((member (first L) (rest L)) (elim (rest L)))
+ ((cons (first L) (elim (rest L))))))
+(println "elim/unique")
+(println (elim C))
+(println (unique C))
+
+(define (reverseL L)
+ (cond
+ ((null? L) '())
+ ((append (reverseL (rest L)) (list (first L))))))
+(println "reverseL/reverse")
+(println (reverseL L))
+(println (reverse L))
+
+(define (list< N L)
+ (cond
+ ((null? L) '())
+ ((>= (first L) N) (list< N (rest L)))
+ ((cons (first L) (list< N (rest L))))))
+(println "list<")
+(println (list< 5 L))
+(println (list< 5 C))
+
+(define (list>= N L)
+ (cond
+ ((null? L) '())
+ ((< (first L) N) (list>= N (rest L)))
+ ((cons (first L) (list>= N (rest L))))))
+(println "list>=")
+(println (list>= 5 C))
+
+;(trace true)
+
+(define (qsort L)
+ (cond
+ ((null? L) '())
+ ((append
+ ;the pivot is the first element of the list
+ (qsort (list< (first L) (rest L)))
+ (cons (first L) '())
+ (qsort (list>= (first L) (rest L)))))))
+(println "qsort")
+(println (qsort C))
+
+;(trace nil)
+
+;we suppose both lists are flat
+(setq L1 '(A ? ? B C D ?))
+(setq L2 '(? A B ? C ? ? D))
+
+;(println "replace")
+;(println L1)
+;(println L2)
+;the replace function modify the passed argument
+;(println (replace 'B L1))
+;(println (replace '? L1))
+;(println (replace '? L2))
+;(println L1)
+;(println L2)
+
+(define (filtre L1 L2 C)
+ ;the replace function modify the passed argument
+ ;FIXME: use the function argument C
+ (replace '? L1)
+ (replace '? L2)
+ (cond
+ ((and (null? L1) (null? L2)) true)
+ ((and (not (null? L1)) (null? L2)) nil)
+ ((and (null? L1) (not (null? L2))) nil)
+ ((and (inclu L1 L2) (inclu L2 L1) true))))
+(println "filtre")
+(println (filtre L1 L2 ?))
+(println (filtre L M ?))
+
+;algorithm written on the board
+(define (filtrerec L1 L2 C)
+ ;FIXME: use the function argument C
+ (cond
+ ((null? L1)
+ (cond
+ ((null? L2) true)
+ ((= '? (first L2)) (filtrerec L1 (rest L2)))
+ (nil)))
+ ((null? L2) (filtrerec L2 L1))
+ ((= '? (first L1)) (filtrerec (rest L1) L2))
+ ((= '? (first L2)) (filtrerec L1 (rest L2)))
+ ((= (first L1) (first L2)) (filtrerec (rest L1) (rest L2)) )
+ (nil)))
+(println "filtrerec")
+(println (filtrerec L1 L2 ?))
+(println (filtrerec L M ?))
+