RosettaCodeData/Task/Closest-pair-problem/Elixir/closest-pair-problem.elixir

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defmodule Closest_pair do
def bruteForce([p0,p1|_] = points) do
pnts = List.to_tuple(points)
minDist = distance(p0, p1)
n = tuple_size(pnts)
{minDistance, minPoints} = Enum.reduce(0..n-2, {minDist, [0,1]}, fn i,{mD,mP} ->
Enum.reduce(i+1..n-1, {mD,mP}, fn j,{md,mp} ->
dist = distance(elem(pnts,i), elem(pnts,j))
if dist < md, do: {dist, [i,j]}, else: {md,mp}
end)
end)
{:math.sqrt(minDistance), minPoints}
end
defp distance({p0x,p0y}, {p1x,p1y}) do
(p1x - p0x) * (p1x - p0x) + (p1y - p0y) * (p1y - p0y)
end
end
data = [{0.654682, 0.925557}, {0.409382, 0.619391}, {0.891663, 0.888594}, {0.716629, 0.996200},
{0.477721, 0.946355}, {0.925092, 0.818220}, {0.624291, 0.142924}, {0.211332, 0.221507},
{0.293786, 0.691701}, {0.839186, 0.728260}]
IO.inspect Closest_pair.bruteForce(data)