clpfd

Look at the following goals (I am using swi-prolog with clpfd from Markus Triska): result(Input,Result) :- Input #> 10, Result=decline. result(Input,Result) :- Input in 0..20, Result=offer. A possible query looks like this: ?- result(15,B). B = decline ; B = offer. I want to add an order or some sort of solution priority. If "decline" is a valid response for Input=15 , then the second goal should not be considered anymore, so that only B=decline is a solution but not B=offer . I know that I could add a !/0 but then the other way round would not work. Give me all possible answers for this

I am working on a small prolog application to solve the Skyscrapers and Fences puzzle. An unsolved puzzle: A solved puzzle: When I pass the program already solved puzzles it is quick, almost instantaneous, to validate it for me. When I pass the program really small puzzles (2x2, for example, with modified rules, of course), it is also quite fast to find a solution. The problem is on computing puzzles with the "native" size of 6x6. I've left it running for 5 or so hours before aborting it. Way too much time. I've found that the part that takes the longest is the "fences" one, not the

I'm trying to solve a constraint processing problem in prolog. I need to pack 4 squares of 5x5,4x4,3x3 and 2x2 in a grid of 10x10. They may not overlap. My variables look like this: Name: SqX(i), i=1..10, domain: 1..10 Where X is either 5,4,3 or 2. The index i represents the row, the domain the column in the grid. My first constraints try to define the width and height of the squares. I formulate it as such: Constraint: SqX(i) > SqX(j)-X /\ i>j-X, range: i>0 /\ j>0 So that the possible points are constrained to be within X rows and columns from each other. Prolog however, stops on these

This question starts from Mat's answer to Algorithm improvement for enumerating binary trees which has only one input value that determines the number of all nodes for the binary tree, and the need to be able to have two input values with one being the number of unary nodes and the other being the number of binary nodes. While I was able to derive a solution by using listing/1 and threading extra state variables: e(t, B, B, U, U). e(u(E), B0, B1, [_|U0], U1) :- e(E, B0, B1, U0, U1). e(b(E0, E1), [_|B0], B2, U0, U2) :- e(E0, B0, B1, U0, U1), e(E1, B1, B2, U1, U2). e(U,B,Es) :- length(Bs, B),