【LeetCode】561.Array Partition I解题报告

【LeetCode】561.Array Partition I解题报告

tags: Array

题目地址：https://leetcode.com/problems/array-partition-i/#/description
题目描述：

  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.

Example1:

Input:
  [1,4,3,2]
Output: 4
Explanation: n is 2, and the maximum sum of pairs is 4.

Note：

  1. n is a positive integer, which is in the range of [1, 10000].
  2. All the integers in the array will be in the range of [-10000, 10000].

Solutions:

public class Solution {    public int arrayPairSum(int[] nums) {      Arrays.sort(nums);          int sum=0;          for(int i=0; i<nums.length; i+=2){              sum += nums[i];          }          return sum;        }}

  此题将给的2n个数，两两凑成一对，使最后的每对的两个数的最小值求和的值最大。方法是尽量小的数和小的数凑成一对，大的数和大的数凑成一对，那么这里涉及到排序，相加即可。

Date：2017年5月25日