✅Easiest Solution🔥||O(N)🔥||Beginner Friendly✅🔥
Intuition\n\n   - The code uses a HashSet named hs to store unique values from the input array nums. This ensures that we only consider each value once, avoidin
# Intuition\n\n   - The code uses a `HashSet` named `hs` to store unique values from the input array `nums`. This ensures that we only consider each value once, avoiding duplicate checks.\n   - It then iterates through each value `valu` in the `HashSet`.\n   - For each `valu`, it checks if its negation `-valu` exists in the `HashSet`. If it does, it updates the maximum value `max` if `valu` is greater than the current `max`.\n   - Finally, it returns the maximum value `max` satisfying the condition.\n\n\n# Complexity\n- Time complexity:\n$$O(n)$$\n\n- Space complexity:\n$$O(n)$$\n\n# Code\n```\nclass Solution {\n    public int findMaxK(int[] nums) {\n\n        HashSet <Integer> hs= new HashSet<>();\n\n        for(int num : nums)\n        {\n            hs.add(num);\n        }\n\n        int max = -1;\n\n        for(int valu : hs)\n        {\n            if(hs.contains(valu*-1))\n            {\n                if(max<valu)\n                    max=valu;\n            }\n        }\n\n        return max;\n    }\n}\n```
['Array', 'Hash Table', 'Two Pointers', 'Sorting', 'Java']