leetcode:4Sum

class Solution {
public:
    vector<vector<int> > fourSum(vector<int> &num, int target) {
  vector<vector<int>> result;
  result.clear();
  sort(num.begin(),num.end());   
  
  int i,j,cur;
  for(i=0;i<num.size();i++)
  {
      if(i>0 && num[i]==num[i-1]) continue;
     for(j=i+1;j<num.size();j++)
     {
         if(j>i+1 && num[j]==num[j-1]) continue;
         
         int k,m;
         k=j+1;
         m=num.size()-1;
         while(k<m)
         {
           if(k>j+1 && num[k]==num[k-1])
           {
              k++;
              continue;
           }
           if(m<num.size()-1 && num[m]==num[m+1])
           {
             m--;
             continue;
           }
           
           cur=num[i]+num[j]+num[k]+num[m];
           if(cur==target) 
           {
            vector<int> tmp;
            tmp.push_back(num[i]);
            tmp.push_back(num[j]);
            tmp.push_back(num[k]);
            tmp.push_back(num[m]);
            result.push_back(tmp);
            k++;
            m--;
           }
           else if(cur<target) k++;
           else m--;  
          }
     }
  }
  return result;  

    }
};