3sum leetcode

class Solution {
    public List<List<Integer>> threeSum(int[] nums) {
       List< List<Integer>> res=new ArrayList<>(); // Creating 2d List
        Arrays.sort(nums);    // sort the Array
        for(int i=0;i<nums.length;i++){    // Iterate on Array
              if(i>0 && nums[i]==nums[i-1])   // Skip Dublicate
                continue;
            int j=i+1;            // Two pointer Approch (j And K)
            int k=nums.length-1;
            while(j<k){
                int sum=nums[i]+nums[j]+nums[k];    // calculate the Total
              if(sum>0)           
              k--;
              if(sum<0)
              j++;
                if(sum==0){
              res.add(Arrays.asList(nums[i], nums[j], nums[k]));    // Add Array to List
              j++;
              k--;
              while(  j<k && nums[j]== nums[j-1])   // Skip the Dublicate Element
              j++;
              while(  j<k && nums[k]==nums[k+1] )   // Skip the Dublicate Element
              k--;
                }
            }
        }
        return res;
    }
}