I am attempting to make a Vector Calculator, that will take either
coordinates, or an already given vector. The if and elsif blocks work
fine, it is the else block that I am in need of help in. I want the code
to re-run from the "answer = gets.chomp.to_i" line if the answer does
not equate to "given" or "coordinates", but when i run the code I am
given the following errors:

vector_calc.rb:48: warning: string literal in condition
vector_calc.rb:51: warning: string literal in condition
vector_calc.rb:50: Invalid retry
vector_calc.rb: compile error (SyntaxError)

The code is below.

puts "Are the vectors given, or do you only know coordinates?"
puts "Please answer either 'given' or 'coordinates'."

begin
answer = gets.chomp.downcase

  if answer == "coordinates"
    puts "What is the x-value of your first coordinate?"
    x1 = gets.chomp.to_i

    puts "What is the y-value of your first coordinate?"
    y1 = gets.chomp.to_i

    puts "What is the x-value of your second coordinate?"
    x2 = gets.chomp.to_i

    puts "What is the y-value of your second coordinate?"
    y2 = gets.chomp.to_i

    coord_1 = [x1, y1]
    coord_2 = [x2, y2]

    puts "Point A = (#{x1}, #{y1})"
    puts "Point B = (#{x2}, #{y2})"

  elsif answer == "given"
    puts "What is vector A's x-value?"
    vect_Ax = gets.chomp.to_i

    puts "what is vector A's y-value?"
    vect_Ay = gets.chomp.to_i

    vect_A = [vect_Ax, vect_Ay]

    puts "What is vector B's x-value?"
    vect_Bx = gets.chomp.to_i

    puts "what is vector B's y-value?"
    vect_By = gets.chomp.to_i

    vect_B = [vect_Bx, vect_By]

    puts "Vector A = [#{vect_Ax}, #{vect_Ay}]"
    puts "Vector B = [#{vect_Bx}, #{vect_By}]"
  else
      if answer != "given" || "coordinates"
        then puts "Please answer either 'given' or 'coordinates'."
      end
    until answer == "coordinates" || "given"
      retry
    end
  end
end


P.S I am creating this code as part of an outcome to a research project,
and am asking your permission to use your answer to this question as
evidence to my folio.

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