[561] Array Partition I

https://leetcode.com/problems/array-partition-i/description/

• algorithms
• Easy (67.49%)
• Source Code: 561.array-partition-i.py
• Total Accepted: 137.6K
• Total Submissions: 200.4K
• Testcase Example: '[1,4,3,2]'

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(object):
    def arrayPairSum(self, nums):
        """
        :type nums: List[int]
        :rtype: int
        """
        if not nums: return 0
        nums.sort()
        lenn = len(nums)
        return sum([min(nums[i], nums[i+1]) for i in range(0, lenn, 2)])