leetcode 561 Array Partition I -Java(Arrays.sort())

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].

题意：2n个整数分为n组，2个数一组，取每组中的较小数，设计分组使所有较小数加和最大。

思路：用sort将数组从小到大排列，取奇数位（即索引偶数位）

bug:思路简单，粗心bug

import java.util.Arrays;//后面使用Arrays.sort

class Solution {
    public int arrayPairSum(int[] nums) {
        int sum = 0;
        Arrays.sort(nums);//默认从小到大
        for(int i=0;i<nums.length;i++){
            if(i%2==0){//0%2==0
                sum = sum + nums[i];//注意是nums[i]，粗心写成i，还没发现
            }
        }
        return sum;
    }
}