Ruby reorder an array based on the contents of a subset array -

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i have array ordered hash[:points]

original = [{a: "bill", points: 4}, {b: "will", points: 3}, {c: "gill", points: 2}, {d: "pill", points: 1}]

i want change order of it's elements based on order of subset array, ordered hash[:points].

subset = [{c: "gill", points: 2}, {b: "will", points: 1}]

the subset's elements contained in original. subset's length , order come @ random. may have two, three, or 4 elements, in order.

i want incorporate order of subset original array. can done reordering original, or recreating original in correct order. either do. don't want merge them. keys , values in subset not important, order of elements.

for example, above subset should produce this.

# bill , pill retain original position # gill , swap places per ordering of subset [{a: "bill", points: 4}, {c: "gill", points: 2}, {b: "will", points: 3}, {d: "{pill}", points: 1}]

another example subset: [{c: "gill", points: 3}, {b: "will", points: 2}, {a: "bill", points: 1}]

# pill remains @ index 3 since not in subset # gill, will, , bill reordered based on order of subset  [{c: "gill", points: 3}, {b: "will", points: 2}, {a: "bill", points: 1}, {d: "pill", points: 1}]

i've tried bunch of stuff past couple of hours, i'm finding harder looks.

my solution has 2 steps:

  1. collect relevant elements original array, , sort them according subset order.
  2. replace them in original array new order.

here code:

mapped_elements = subset.map { |i| original.find { |j| j.keys == i.keys } }  result = original.map |i|   if subset.find { |j| j.keys == i.keys }     mapped_elements.shift   else       end end

for subset = [{c: "gill", points: 2}, {b: "will", points: 1}] result be:

[{a: "bill", points: 4}, {c: "gill", points: 2}, {b: "will", points: 3}, {d: "{pill}", points: 1}]

for subset = [{c: "gill", points: 3}, {b: "will", points: 2}, {a: "bill", points: 1}] result be:

[{c: "gill", points: 3}, {b: "will", points: 2}, {a: "bill", points: 4}, {d: "pill", points: 1}]

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