Leetcode#40 Combination Sum II

原题地址

排序+DFS

代码：

vector<vector<int> > res;
    
void dfs(vector<int> &num, vector<int> &ans, int pos, int left) {
  if (left == 0)
    res.push_back(ans);
  for (int i = pos; i < num.size() && num[i] <= left; i++) {
    if (i == pos || num[i] > num[i - 1]) {
      ans.push_back(num[i]);
      dfs(num, ans, i + 1, left - num[i]);
      ans.pop_back();
    }
  }
}
    
vector<vector<int> > combinationSum2(vector<int> &num, int target) {
  sort(num.begin(), num.end());
  vector<int> ans;
  dfs(num, ans, 0, target);
  return res;
}