Law of cosines - triples: Difference between revisions
Content deleted Content added
→{{header|JavaScript}}: Edited to collect solutions in a Set object |
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const |
const |
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xs = enumFromTo(1, n), |
xs = enumFromTo(1, n), |
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fr = f(xs.reduce((a, x) => (a[x * x] = x, a), {})), |
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gc = xs.reduce((a, _) => a, {}), |
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xs |
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), |
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dctRoots = foldl( |
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(a, x) => (a[x * x] = x, a), {}, |
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xs |
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), |
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fr = f(dctRoots), |
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setSoln = new Set(); |
setSoln = new Set(); |
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return ( |
return ( |
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xs.forEach( |
xs.forEach( |
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a => { |
a => { |
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const a2 = |
const a2 = a * a; |
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enumFromTo(1, 1 + a).forEach( |
enumFromTo(1, 1 + a).forEach( |
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b => { |
b => { |
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const |
const |
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suma2b2 = a2 + |
suma2b2 = a2 + b * b, |
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c = fr(suma2b2, a * b, a, b); |
c = fr(suma2b2, a * b, a, b); |
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if (undefined !== c) { |
if (undefined !== c) { |
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// GENERIC FUNCTIONS ---------------------------- |
// GENERIC FUNCTIONS ---------------------------- |
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// descending :: a -> a -> Ordering |
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const descending = (a, b) => a < b ? 1 : (a > b ? -1 : 0); |
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// concatMap :: (a -> [b]) -> [a] -> [b] |
// concatMap :: (a -> [b]) -> [a] -> [b] |
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m |
m |
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) : []; |
) : []; |
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// flip :: (a -> b -> c) -> b -> a -> c |
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const flip = f => |
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1 < f.length ? ( |
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(a, b) => f(b, a) |
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) : (x => y => f(y)(x)); |
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// foldl :: (a -> b -> a) -> a -> [b] -> a |
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const foldl = (f, a, xs) => xs.reduce(f, a); |
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// iterateUntil :: (a -> Bool) -> (a -> a) -> a -> [a] |
// iterateUntil :: (a -> Bool) -> (a -> a) -> a -> [a] |
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// length :: [a] -> Int |
// length :: [a] -> Int |
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const length = xs => xs.length || Infinity; |
const length = xs => xs.length || Infinity; |
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// sortBy :: (a -> a -> Ordering) -> [a] -> [a] |
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const sortBy = (f, xs) => |
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xs.slice() |
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.sort(f); |
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// take :: Int -> [a] -> [a] |
// take :: Int -> [a] -> [a] |
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// unlines :: [String] -> String |
// unlines :: [String] -> String |
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const unlines = xs => xs.join('\n'); |
const unlines = xs => xs.join('\n'); |
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// Use of `take` and `length` here allows zipping with non-finite lists |
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// i.e. generators like cycle, repeat, iterate. |
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// Use of `take` and `length` here allows zipping with non-finite lists |
// Use of `take` and `length` here allows zipping with non-finite lists |
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