Untitled

class Solution {
public:
    vector<vector<int>> divideArray(vector<int>& arr, int k) {
        int size=arr.size()/3, n=arr.size();
        if(n%3 !=0 ) return vector<vector<int>>();

        vector<vector<int>>res(size,vector<int>(3));
        sort(arr.begin(),arr.end());

        int ind=0;
        for(int i=0;i<n;i+=3){
            if(i+2<n && arr[i+2]-arr[i]<=k){
                res[ind]={arr[i],arr[i+1],arr[i+2]};
                ind++;
            }
            else if(arr[i+2]-arr[i]>k){
                return vector<vector<int>>();
            }
        }
        return res;  
    }
};