如何让两个选择框在angularjs中反向工作？

<select ng-model="option1" ng-change="updateOption2()">
  <option value="option1Value1">Option 1 Value 1</option>
  <option value="option1Value2">Option 1 Value 2</option>
</select>

<select ng-model="option2" ng-change="updateOption1()">
  <option value="option2Value1">Option 2 Value 1</option>
  <option value="option2Value2">Option 2 Value 2</option>
</select>

angular.module('myApp', [])
  .controller('myController', function($scope) {
    $scope.updateOption2 = function() {
      if ($scope.option1 === 'option1Value1') {
        $scope.option2 = 'option2Value1';
      } else if ($scope.option1 === 'option1Value2') {
        $scope.option2 = 'option2Value2';
      }
    };

    $scope.updateOption1 = function() {
      if ($scope.option2 === 'option2Value1') {
        $scope.option1 = 'option1Value1';
      } else if ($scope.option2 === 'option2Value2') {
        $scope.option1 = 'option1Value2';
      }
    };
  });

<div ng-app="myApp" ng-controller="myController">
  <!-- 在这里放置选择框的代码 -->
</div>