# -*- coding: utf-8 -*-

"""
Given an array of 2n integers, your task is to group these integers into n pairs of integer,
say (a1, b1), (a2, b2), ..., (an, bn) which makes sum of min(ai, bi) for all i from 1 to n as large as possible.

Example 1:
Input: [1,4,3,2]

Output: 4
Explanation: n is 2, and the maximum sum of pairs is 4 = min(1, 2) + min(3, 4).
Note:
n is a positive integer, which is in the range of [1, 10000].
All the integers in the array will be in the range of [-10000, 10000].
"""


class Solution:
    def arrayPairSum(self, nums):
        """
        :type nums: List[int]
        :rtype: int

        >>> test1 = [1,4,3,2]
        >>> s = Solution()
        >>> s.arrayPairSum(test1)
        4

        """
        # 排序然后隔一取值
        l = len(nums)
        nums.sort()
        sum_ = 0
        if l == 2:
            return min(nums)
        for i in range(0, l, 2):
            sum_ += nums[i]
        return sum_
        # return sum(sorted(nums)[::2])


if __name__ == '__main__':
    import doctest
    doctest.testmod(verbose=True)