LeetCode 40. Combination Sum II

struct Node
{
    vector<int> a;
    int sum;
    int index;
    Node(){}
    Node(int index,int sum,vector<int> a)
    {
        this->index = index;
        this->sum = sum;
        this->a = a;
    }
    
};

class Solution {
public:
    queue<Node> q;  
    map<int,int> m;
    vector<vector<int>> combinationSum2(vector<int>& candidates, int target) {
        
        sort(candidates.begin(),candidates.end());
        
        vector<vector<int>> ans;
        for(int i=0;i<candidates.size();i++)
        {
            if(m[candidates[i]]==0)
            {
                vector<int> a;
                  a.push_back(candidates[i]);
                 q.push(Node(i,candidates[i],a));
                m[candidates[i]]=1;
            }
        }
        
        while(!q.empty())
        {
            Node term = q.front();
            q.pop();
            
            if(term.sum==target)
            {
                ans.push_back(term.a);
                continue;
            }
            if(term.sum>target)
            {
                continue;
            }
            m.clear();
            for(int i=term.index+1;i<candidates.size();i++)
            {
                 if(m[candidates[i]]==1)
                    continue;
                if(term.sum+candidates[i]>target)
                    continue;
               
                else if(term.sum+candidates[i]==target)
                {
                     vector<int> x = term.a;
                    x.push_back(candidates[i]);
                    ans.push_back(x);
                    m[candidates[i]]=1;
                }
                else
                {
                    vector<int> x = term.a;
                    x.push_back(candidates[i]);
                    q.push(Node(i,term.sum+candidates[i],x));
                    m[candidates[i]]=1;
                }
            }
        }
        return ans;
    }
};