Courses/CS 460/Fall 2005/Homework/Brian Smith/Oct 22
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< Courses | CS 460 | Fall 2005 | Homework | Brian Smith
From Judy's Logic Problems.
Contents |
[edit] Four Trees
Each of four men who live in Willowbrook Estates on the city’s north side, planted a different type of tree in their front yard on Arbor Day. From The clues, determine the first and last name of each man and the type of tree each planted.
- George, Mr.Clary, and Mr. Becker (who got his tree from HomeTown Garden Center) all live within three blocks of one another.
- Mr. Clary planted neither the cedar tree or the maple tree.
- Harvey and Mr. Clary live next door to one another.
- The ash tree was not planted by neither John nor Ivan.
- The maple tree was not the tree planted by George (who is not surnamed Delgado).
- Mr. Erichsen isn’t the man who planted the ash tree.
- John, who purchased his tree at the Green Thumb Greenhouse, isn’t the man who planted the sycamore.
local
FirstNames = [george harvey ivan john]
SurNames = [becker clary delgado erichsen]
Trees = [ash cedar maple sycamore]
%----- Helper Procedures -----
proc {Append ?Xs ?Ys ?Zs}
choice
Xs = nil
Ys = Zs
[] Head XRest ZRest in
Xs = Head|XRest
Zs = Head|ZRest
{Append XRest Ys ZRest}
end
end
proc {IsAFirstName ?F} {IsAMember F FirstNames} end
proc {IsAMember ?X Xs} {Append _ X|_ Xs} end
proc {IsAPropertyValue Results ?Property ?Value}
{IsAMember Property#Value {Record.toListInd Results}}
end
%----- Clues -----
% Try to assign first names to last names, and first names to trees.
% The helper procedures use IsAMember to provide a choice point, so each
% clue tries to assign all possible choices. Some fail based on the
% restraints in each clue (failed unifications).
% 1.
% george \= clary
% george \= becker
% clary \= becker
proc {Clue1 Results}
F1 F2 in
{IsAFirstName F1}
{IsAFirstName F2}
F1 == george = false
F2 == george = false
F1 == F2 = false
{IsAPropertyValue Results becker F1}
{IsAPropertyValue Results clary F2}
end
% 2.
% clary \= cedar
% clary \= maple
proc {Clue2 Results}
F1 F2 in
{IsAFirstName F1}
{IsAFirstName F2}
F1 == Results.clary = false
F2 == Results.clary = false
F1 == F2 = false
{IsAPropertyValue Results cedar F1}
{IsAPropertyValue Results maple F2}
end
% 3.
% harvey \= clary
proc {Clue3 Results}
Results.clary == harvey = false
end
% 4.
% ash \= john
% ash \= ivan
proc {Clue4 Results}
F in
{IsAFirstName F}
F == john = false
F == ivan = false
F == Results.cedar = false
F == Results.maple = false
{IsAPropertyValue Results ash F}
end
% 5.
% maple \= george
% george \= delgado
proc {Clue5 Results}
F in
Results.maple == george = false
{IsAFirstName F}
F == george = false
F == Results.becker = false
F == Results.clary = false
{IsAPropertyValue Results delgado F}
end
% 6.
% erichsen \= ash
proc {Clue6 Results}
F in
{IsAFirstName F}
F == Results.ash = false
F == Results.becker = false
F == Results.clary = false
F == Results.delgado = false
{IsAPropertyValue Results erichsen F}
end
% 7.
% john \= becker
% john \= sycamore
proc {Clue7 Results}
F in
Results.becker == john = false
{IsAFirstName F}
F == john = false
F == Results.ash = false
F == Results.cedar = false
F == Results.maple = false
{IsAPropertyValue Results sycamore F}
end
%----- Execution -----
fun {FourTrees}
Properties = {FoldR [SurNames Trees] Append nil}
Results = {MakeRecord resultProperties Properties}
in
{Clue1 Results}
{Clue2 Results}
{Clue3 Results}
{Clue4 Results}
{Clue5 Results}
{Clue6 Results}
{Clue7 Results}
Results
end
in
{Browse {SearchAll FourTrees}}
end
[edit] Flower Boxes
Mary and three other women had flower boxes in windows on either side of their front doors and each woman planted a different type of flower in her window flower boxes (one woman planted petunias). From the clues, can you determine the first name and last name (one is Gumble) of each woman and the type of flower each woman planted?
- The four women - Julie, Ms. Drake, Ms. Evans, and the woman who planted daisies, all belong to the same gardening club.
- The woman who planted violets in her flower boxes isn’t Kate.
- Ms. Drake isn’t the woman who planted marigolds.
- Ms. Florez, who didn’t plant violets, is married to Lola’s brother.
- Marigolds were not the flower of choice for Julie.
- Kate, whose surname isn’t Evans, didn’t plant daisies in her window flower boxes.
local
FirstNames = [julie kate lola mary]
SurNames = [drake evans florez gumble]
Flowers = [daisies marigolds petunias violets]
%----- Helper Procedures -----
proc {Append ?Xs ?Ys ?Zs}
choice
Xs = nil
Ys = Zs
[] Head XRest ZRest in
Xs = Head|XRest
Zs = Head|ZRest
{Append XRest Ys ZRest}
end
end
proc {IsAFirstName ?F} {IsAMember F FirstNames} end
proc {IsAMember ?X Xs} {Append _ X|_ Xs} end
proc {IsAPropertyValue Results ?Property ?Value}
{IsAMember Property#Value {Record.toListInd Results}}
end
%----- Clues -----
% Try to assign first names to last names, and first names to flowers.
% The helper procedures use IsAMember to provide a choice point, so each
% clue tries to assign all possible choices. Some fail based on the
% restraints in each clue (failed unifications).
% 1.
% drake \= julie
% evans \= julie
% daisies \= julie
% drake \= daisies
% evans \= daisies
proc {Clue1 Results}
F1 F2 F3 in
{IsAFirstName F1}
{IsAFirstName F2}
{IsAFirstName F3}
F1 == julie = false
F2 == julie = false
F3 == julie = false
F1 == F2 = false
F2 == F3 = false
F1 == F3 = false
{IsAPropertyValue Results drake F1}
{IsAPropertyValue Results evans F2}
{IsAPropertyValue Results daisies F3}
end
% 2.
% violets \= kate
proc {Clue2 Results}
F in
{IsAFirstName F}
F == kate = false
F == Results.daisies = false
{IsAPropertyValue Results violets F}
end
% 3.
% drake \= marigolds
proc {Clue3 Results}
F in
{IsAFirstName F}
F == Results.drake = false
F == Results.daisies = false
F == Results.violets = false
{IsAPropertyValue Results marigolds F}
end
% 4.
% florez \= violets
% florez \= lola
proc {Clue4 Results}
F in
{IsAFirstName F}
F == lola = false
F == Results.violets = false
F == Results.drake = false
F == Results.evans = false
{IsAPropertyValue Results florez F}
end
% 5.
% marigolds \= julie
proc {Clue5 Results}
Results.marigolds == julie = false
end
% 6.
% evans \= kate
% daisies \= kate
proc {Clue6 Results}
Results.evans == kate = false
Results.daisies == kate = false
end
% Cleanup
% Some properties are not explicitly set in the clues. I run this proc
% after the clues to insert whatever values are left.
proc {Remainder Results}
F1 F2 in
% assign a first name to Gumble
{IsAFirstName F1}
F1 == Results.drake = false
F1 == Results.evans = false
F1 == Results.florez = false
{IsAPropertyValue Results gumble F1}
% assign a first name to petunias
{IsAFirstName F2}
F2 == Results.daisies = false
F2 == Results.marigolds = false
F2 == Results.violets = false
{IsAPropertyValue Results petunias F2}
end
%----- Execution -----
fun {FlowerBoxes}
Properties = {FoldR [SurNames Flowers] Append nil}
Results = {MakeRecord resultProperties Properties}
in
{Clue1 Results}
{Clue2 Results}
{Clue3 Results}
{Clue4 Results}
{Clue5 Results}
{Clue6 Results}
{Remainder Results}
Results
end
in
{Browse {SearchAll FlowerBoxes}}
end
