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.
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]
Solution：
class Solution {
public:
int arrayPairSum(vector<int>& nums) {
int sum = 0;
sort(nums.begin(),nums.end()) ;
for(int i=0; i<nums.size(); i+=2) {
sum += nums[i];
}
return sum;
}
};
public:
int arrayPairSum(vector<int>& nums) {
int sum = 0;
sort(nums.begin(),nums.end()) ;
for(int i=0; i<nums.size(); i+=2) {
sum += nums[i];
}
return sum;
}
};