Given two arrays, write a function to compute their intersection.

Example:
Given nums1 = [1, 2, 2, 1], nums2 = [2, 2], return [2].

Note:
Each element in the result must be unique.
The result can be in any order.

利用数组的indexof

var intersection = function(nums1, nums2) {
    var num1 = nums1.length;
    var num2 = nums2.length;
    return num1 < num2 ? compare(nums1,nums2,num1) : compare(nums2,nums1,num2);
    function compare(a,b,num) {
        var result = [];
        for (var i = 0;i<num;i++){
            if (result.indexOf(a[i])===-1) {
                if (b.indexOf(a[i])!==-1) {
                    result.push(a[i]);
                }
            }
        }
        return result;
    }
};