Initial data commit

Task/Knapsack-problem-Continuous/Erlang/knapsack-problem-continuous.erl

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+-module( knapsack_problem_continuous ).
+
+-export( [price_per_weight/1, select/2, task/0] ).
+
+price_per_weight( Items ) -> [{Name, Weight, Price / Weight} || {Name, Weight, Price} <-Items].
+
+select( Max_weight, Items ) ->
+	{_Remains, Selected_items} = lists:foldr( fun select_until/2, {Max_weight, []}, lists:keysort(3, Items) ),
+	Selected_items.
+
+task() ->
+	Items = items(),
+	io:fwrite( "The robber takes the following to maximize the value~n" ),
+	[io:fwrite("~.2f of ~p~n", [Weight, Name]) || {Name, Weight} <- select( 15, price_per_weight(Items) )].
+
+
+
+items() ->
+	[{"beef", 3.8, 36},
+	{"pork", 5.4, 43},
+	{"ham", 3.6, 90},
+	{"greaves", 2.4, 45},
+	{"flitch", 4.0, 30},
+	{"brawn", 2.5, 56},
+	{"welt", 3.7 , 67},
+	{"salami", 3.0, 95},
+	{"sausage",  5.9 , 98}
+	].
+
+select_until( {Name, Weight, _Price}, {Remains, Acc} ) when Remains > 0 ->
+	Selected_weight = select_until_weight( Weight, Remains ),
+	{Remains - Selected_weight, [{Name, Selected_weight} | Acc]};
+select_until( _Item, Acc ) -> Acc.
+
+select_until_weight( Weight, Remains ) when Weight < Remains -> Weight;
+select_until_weight( _Weight, Remains ) -> Remains.