title: Count Possible Ways To Construct Buildings
signature: function count_possible_ways_to_construct_buildings(n)
source_py: def count_possible_ways_to_construct_buildings(N):
      if (N == 1):
          return 4
      countB = 1
      countS = 1
      for i in range(2, (N + 1)):
          prev_countB = countB
          prev_countS = countS
          countS = (prev_countB + prev_countS)
          countB = prev_countS
      result = (countS + countB)
      return (result * result)
source_cpp: int count_possible_ways_to_construct_buildings(int N) {
    if ( N == 1 ) return 4;
    int countB = 1, countS = 1, prev_countB, prev_countS;
    for ( int i = 2;
    i <= N;
    i ++ ) {
      prev_countB = countB;
      prev_countS = countS;
      countS = prev_countB + prev_countS;
      countB = prev_countS;
    }
    int result = countS + countB;
    return ( result * result );
  }
question_info.entry_fn_name: count_possible_ways_to_construct_buildings
question_info.entry_cls_name: Solution
question_info.test_case_ids: ['0', '1', '2']
question_info.test_code: 
  
  -- SOLUTION CODE
  -- ============================================
  PLACEHOLDER_CODE_BODY
  
  -- TESTING CODE 
  -- ============================================
  function isCorrect(actual, expected)
      if type(expected) ~= type(actual) then
          return false
      end
      
      if type(expected) == 'table' then
          for k,v_expected in pairs(expected) do
              
              if actual[k] == nil then
                  return false
              end
              local v_actual = actual[k]
              if not isCorrect(v_actual, v_expected) then
                  return false
              end
              actual[k]=nil
          end
      
          if next(actual) then 
              return false
          end
          return true
      else
          return actual == expected
      end
  end
  
  function validateSolution(actual, expected)
      return isCorrect(actual,expected)
  end
  
  function driver(n, expected)
      local exec_result;
      local status, error_msg = pcall(function () 
          exec_result=PLACEHOLDER_FN_NAME(n) 
      end)
      if status then
          if validateSolution(exec_result,expected) then
              return "PASSED"
          end
          return "FAILED"
      else
          return string.format("ERROR=%s",string.gsub(error_msg,".*:[%d]+: ",""))
      end
  end
      
  function main()
      result = driver(17, 17480761)
      print(string.format("TEST-0...%s",result))
  
      result = driver(34, 222915410843904)
      print(string.format("TEST-1...%s",result))
  
      result = driver(9, 7921)
      print(string.format("TEST-2...%s",result))
  
  end
  
  main()
question_info.test_list: [{"idx": 0, "outputs": 17480761, "inputs": {"n": 17}}, {"idx": 1, "outputs": 222915410843904, "inputs": {"n": 34}}, {"idx": 2, "outputs": 7921, "inputs": {"n": 9}}]