题目

Compare two arrays and return a new array with any items only found in one of the two given arrays, but not both. In other words, return the symmetric difference of the two arrays.
Remember to use Read-Search-Ask if you get stuck. Try to pair program. Write your own code.

Here are some helpful links:
Comparison Operators

Array.prototype.slice()

Array.prototype.filter()

Array.prototype.indexOf()

Array.prototype.concat()

given code

function diffArray(arr1, arr2) {
  var newArr = [];
  // Same, same; but different.
  return newArr;
}
diffArray([1, 2, 3, 5], [1, 2, 3, 4, 5]);

• 遍历arr1
• 在遍历arr1的时候遍历arr2。比较两个元素是否全等。如果全等，那么两个元素的下标都加一，如果不等，则把