Class: Lahcuby::Solver

Inherits:
Object
  • Object
show all
Defined in:
lib/lahcuby/solver.rb

Instance Method Summary collapse

Constructor Details

#initialize(initial_solution, maximum_number_of_iterations, memory_size) ⇒ Solver

Returns a new instance of Solver.



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# File 'lib/lahcuby/solver.rb', line 4

def initialize(initial_solution, maximum_number_of_iterations, memory_size)
  @current_solution = initial_solution
  @maximum_number_of_iterations = maximum_number_of_iterations
  @memory_size = memory_size
end

Instance Method Details

#solve ⇒ Object 



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# File 'lib/lahcuby/solver.rb', line 10

def solve()
  costs_memory = []
  @memory_size.times do |_|
    costs_memory.push(@current_solution.get_cost)
  end
  best_solution = @current_solution

  @maximum_number_of_iterations.times do |iteration|
    memory_index = iteration % @memory_size
    new_solution = @current_solution.get_variation

    beats_current_solution =
        new_solution.get_cost < @current_solution.get_cost
    memory_cost = costs_memory[memory_index]
    beats_memory_cost = new_solution.get_cost < memory_cost

    if beats_current_solution || beats_memory_cost
      @current_solution = new_solution
    end

    if beats_memory_cost
      costs_memory[memory_index] = new_solution.get_cost
    end

    if @current_solution.get_cost < best_solution.get_cost
      best_solution = @current_solution
    end
  end

  best_solution
end