Data commit

Task/Knapsack-problem-Bounded/EchoLisp/knapsack-problem-bounded-1.l

@@ -0,0 +1,54 @@
+(lib 'struct)
+(lib 'sql)
+(lib 'hash)
+
+(define H (make-hash))
+(define T (make-table (struct goodies (name poids valeur qty))))
+(define IDX (make-vector 0))
+
+
+;; convert to 0/1 PB
+;; transorm vector [1 2 3 4 (n-max 3) 5 (n-max 2) 6 .. ]
+;; into vector of repeated indices : [1 2 3 4 4 4 5 5 6 ... ]
+
+(define (make-01 T)
+	 (for ((record T) (i (in-naturals)))
+		 (for ((j (in-range 0 (goodies-qty record))))
+			 (vector-push IDX i)))
+	 IDX)
+	
+(define-syntax-rule (name i) (table-xref T (vector-ref IDX i) 0))
+(define-syntax-rule (poids i) (table-xref T (vector-ref IDX i) 1))
+(define-syntax-rule (valeur i) (table-xref T (vector-ref IDX i) 2))
+
+;;
+;; code identical to 0/1 problem	
+;;
+
+;;  make an unique hash-key from (i rest)
+(define (t-idx i r)  (string-append i "|" r))
+;; retrieve best core for item i, remaining r availbble weight
+(define (t-get i r)  (or (hash-ref H (t-idx i r)) 0))
+
+;; compute best score (i), assuming best (i-1 rest) is known
+(define (score i restant)
+	 (if (< i 0) 0
+	 (hash-ref! H (t-idx i restant)
+		 (if ( >= restant (poids i))
+			 (max
+			 (score (1- i) restant)
+			 (+ (score (1- i) (- restant (poids i))) (valeur i)))
+		    (score (1- i) restant)) ;; else not enough
+	)))
+	
+;; compute best scores, starting from last item
+(define (task W)
+        (define restant W)
+        (make-01 T)
+        (define N (1- (vector-length IDX)))
+		 (writeln 'total-value (score N W))
+		 (group
+		 (for/list  ((i (in-range N -1 -1)))
+		 #:continue (= (t-get i restant) (t-get (1- i) restant))
+		(set! restant (- restant (poids i)))
+		(name i))))

Task/Knapsack-problem-Bounded/EchoLisp/knapsack-problem-bounded-2.l

@@ -0,0 +1,19 @@
+(define goodies
+    '((map  9 150 1) (compass 13 35 1)(water 153 200 3)
+ (sandwich 50 60 2)(🍰-glucose 15 60 2)(tin  68 45 3)
+ (🍌-banana  27 60 3)(🍎-apple 39 40 3)(cheese 23 30 1)
+ (beer 52 10 3)(🌞-suntan-cream  11  70 1)(camera 32 30 1)
+ (t-shirt 24 15 2)(trousers 48 10 2)(umbrella 73 40 1)
+ (☔️-trousers  42 70 1)(☔️--overcoat 43 75 1)(note-case 22 80 1)
+ (🌞-sunglasses 7 20 1)(towel 18 12 2)(socks 4 50 1)
+ (book 30 10 2)))
+
+(list->table goodies T)
+
+(task 400)
+total-value     1010
+   → ((socks) (🌞-sunglasses) (note-case) (☔️--overcoat) (🌞-suntan-cream) (cheese)
+ (🍌-banana 🍌-banana 🍌-banana) (🍰-glucose 🍰-glucose) (water) (compass) (map))
+
+(length (hash-keys H))
+    → 10827 ;; # of entries in cache