2441_Largest_Positive_Integer_That_Exists_With_Its_Negative.cpp

/*
2441. Largest Positive Integer That Exists With Its Negative
Given an integer array nums that does not contain any zeros, find the largest positive integer k such that -k also exists in the array.
Return the positive integer k. If there is no such integer, return -1.
Example 1:
Input: nums = [-1,2,-3,3]
Output: 3
Explanation: 3 is the only valid k we can find in the array.
Example 2:
Input: nums = [-1,10,6,7,-7,1]
Output: 7
Explanation: Both 1 and 7 have their corresponding negative values in the array. 7 has a larger value.
Example 3:
Input: nums = [-10,8,6,7,-2,-3]
Output: -1
Explanation: There is no a single valid k, we return -1.
Constraints:
1 <= nums.length <= 1000
-1000 <= nums[i] <= 1000
nums[i] != 0
*/
class Solution {
public:
    int findMaxK(vector<int>& nums) {
        sort(nums.begin(),nums.end());
        int i = 0 , j = nums.size()-1;
        while(i<j){
            int sum = nums[i]+nums[j];
            if(sum==0){
                if(abs(nums[i] && abs(nums[j]))){return max(nums[i],nums[j]);}
            }
            else if(sum<0){
                i++;
            }
            else{
                j--;
            }
        }
        return -1;
    }
};