McNuggets problem: Difference between revisions
→{{header|Applescript}}: Added an Applescript draft
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number (a number ''n'' which cannot be expressed with ''6x + 9y + 20z = n''
where ''x'', ''y'' and ''z'' are natural numbers).
=={{header|AppleScript}}==
Generalised for other set sizes, and for other triples of natural numbers. Uses NSMutableSet, through the AppleScript ObjC interface:
<lang applescript>use AppleScript version "2.4"
use framework "Foundation"
use scripting additions
on run
set setNuggets to mcNuggetSet(100, 6, 9, 20)
script isMcNugget
on |λ|(x)
setMember(x, setNuggets)
end |λ|
end script
set xs to dropWhile(isMcNugget, enumFromThenTo(100, 99, 1))
set setNuggets to missing value -- Clear ObjC pointer value
if 0 < length of xs then
item 1 of xs
else
"No unreachable quantities in this range"
end if
end run
-- mcNuggetSet :: Int -> Int -> Int -> Int -> ObjC Set
on mcNuggetSet(n, mcx, mcy, mcz)
set upTo to enumFromTo(0)
script fx
on |λ|(x)
script fy
on |λ|(y)
script fz
on |λ|(z)
set v to sum({mcx * x, mcy * y, mcz * z})
if 101 > v then
{v}
else
{}
end if
end |λ|
end script
concatMap(fz, upTo's |λ|(n div mcz))
end |λ|
end script
concatMap(fy, upTo's |λ|(n div mcy))
end |λ|
end script
setFromList(concatMap(fx, upTo's |λ|(n div mcx)))
end mcNuggetSet
-- GENERIC FUNCTIONS ----------------------------------------------------
-- concatMap :: (a -> [b]) -> [a] -> [b]
on concatMap(f, xs)
set lng to length of xs
set acc to {}
tell mReturn(f)
repeat with i from 1 to lng
set acc to acc & |λ|(item i of xs, i, xs)
end repeat
end tell
return acc
end concatMap
-- drop :: Int -> [a] -> [a]
-- drop :: Int -> String -> String
on drop(n, xs)
set c to class of xs
if c is not script then
if c is not string then
if n < length of xs then
items (1 + n) thru -1 of xs
else
{}
end if
else
if n < length of xs then
text (1 + n) thru -1 of xs
else
""
end if
end if
else
take(n, xs) -- consumed
return xs
end if
end drop
-- dropWhile :: (a -> Bool) -> [a] -> [a]
-- dropWhile :: (Char -> Bool) -> String -> String
on dropWhile(p, xs)
set lng to length of xs
set i to 1
tell mReturn(p)
repeat while i ≤ lng and |λ|(item i of xs)
set i to i + 1
end repeat
end tell
drop(i - 1, xs)
end dropWhile
-- enumFromThenTo :: Int -> Int -> Int -> [Int]
on enumFromThenTo(x1, x2, y)
set xs to {}
repeat with i from x1 to y by (x2 - x1)
set end of xs to i
end repeat
return xs
end enumFromThenTo
-- enumFromTo :: Int -> Int -> [Int]
on enumFromTo(m)
script
on |λ|(n)
if m ≤ n then
set lst to {}
repeat with i from m to n
set end of lst to i
end repeat
return lst
else
return {}
end if
end |λ|
end script
end enumFromTo
-- foldl :: (a -> b -> a) -> a -> [b] -> a
on foldl(f, startValue, xs)
tell mReturn(f)
set v to startValue
set lng to length of xs
repeat with i from 1 to lng
set v to |λ|(v, item i of xs, i, xs)
end repeat
return v
end tell
end foldl
-- Lift 2nd class handler function into 1st class script wrapper
-- mReturn :: First-class m => (a -> b) -> m (a -> b)
on mReturn(f)
if class of f is script then
f
else
script
property |λ| : f
end script
end if
end mReturn
-- sum :: [Num] -> Num
on sum(xs)
script add
on |λ|(a, b)
a + b
end |λ|
end script
foldl(add, 0, xs)
end sum
-- NB All names of NSMutableSets should be set to *missing value*
-- before the script exits.
-- ( scpt files can not be saved if they contain ObjC pointer values )
-- setFromList :: Ord a => [a] -> Set a
on setFromList(xs)
set ca to current application
ca's NSMutableSet's ¬
setWithArray:(ca's NSArray's arrayWithArray:(xs))
end setFromList
-- setMember :: Ord a => a -> Set a -> Bool
on setMember(x, objcSet)
missing value is not (objcSet's member:(x))
end setMember</lang>
{{Out}}
<pre>43</pre>
=={{header|C}}==
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