示例#1
0
 /**
  * @param num: Given the candidate numbers
  * @param target: Given the target number
  * @return: All the combinations that sum to target
  */
 vector<vector<int>> combinationSum2(vector<int> &num, int target) {
     sort(num.begin(), num.end());
     vector<vector<int>> ans;
     vector<int> v;
     combinationSum2Helper(num, target, 0, v, ans);
     return ans;
 }
 vector<vector<int>> combinationSum2(vector<int>& candidates, int target) {
     sort(candidates.begin(), candidates.end());
     vector<vector<int>> res;
     vector<int> comb;
     combinationSum2Helper(candidates, target, res, comb, 0);
     return res;
 }
 void combinationSum2Helper(vector<int>& candidates, int target, vector<vector<int>>& res, vector<int>& comb, int begin) {
     if(target == 0) {
         res.push_back(comb);
     }
     for(int i = begin; i < candidates.size() && target >= candidates[i]; i++) {
         if(i > begin && candidates[i] == candidates[i-1]) {
             continue;
         }
         comb.push_back(candidates[i]);
         combinationSum2Helper(candidates, target - candidates[i], res, comb, i+1);
         comb.pop_back();
     }
 }
示例#4
0
    void combinationSum2Helper(vector<int>& num, int gap, int begin,
                               vector<int>& v,vector<vector<int>> &ans) {
        if (gap == 0) {
            ans.emplace_back(v);
            return;
        }

        for (size_t i = begin; i < num.size() && num[i] <= gap; ++i) {
            if ( i == begin || num[i] != num[i - 1]) {  // Skip duplicates.
                // Each same element could be chosen only once
                // with the same previous nums.
                v.emplace_back(num[i]);
                combinationSum2Helper(num, gap - num[i], i + 1, v, ans);
                v.pop_back();
            }
        }
    }
示例#5
0
	void backtarck(vector<vector<int> >res, vector<bool> flag,vector<int> tmp, vector<int> candidates,int target)
	{
		if(target == 0)
		{
			bool found = false;
			for(vector<vector<int> >::iterator it = res.begin(); it!= res.end();it++)
			{
				if(tmp == *it)
				{
					found = true;
					break;
				}
			}
			if(!found)
				res.push_back(tmp);
			return;
		}
		else if (target < 0)
		{
			return;
		};
		int max = 0;
		for (int i = 0; i < tmp.size(); ++i)
		{
			if(tmp[i] > max)
				max = tmp[i]
		}
		for (int i = 0; i < candidates.size(); ++i)
		{
			if(!flag[i] && candidates[i] >= max)
			{
				flag[i] = true;
                tmp.push_back(candidates[i]);
                combinationSum2Helper(ans, flag, tmp, candidates, target - candidates[i]);
                tmp.pop_back();
                flag[i] = false;
			}
		}
	}