(Easy) Array Partition I - LeetCode

Description:

Given an array of 2n integers, your task is to group these integers into n pairs of integer, say (a₁, b₁), (a₂, b₂), ..., (a_n, b_n) which makes sum of min(a_i, b_i) 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:

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].

 

Accepted

161,458

Submissions

231,095

 

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Solution:

class Solution {
    public int arrayPairSum(int[] nums) {
        if(nums==null||nums.length ==0){
            return 0;
        }
        
        Arrays.sort(nums);
        int Sum = 0; 
        for(int i = nums.length-2; i>=0; i=i-2){
            
            Sum = Sum + nums[i];
            
        }
        
        return Sum; 
    }
}