在二元树中找出和为某一值的所有路径

struct BinaryTreeNode
{
int m_nValue;
BinaryTreeNode *m_pLeft;
BinaryTreeNode *m_pRight;
};
void FindPath (BinaryTreeNode *pTreeNode, int expectedSum,
vector<int> &path, int ¤tSum)
{
if (pTreeNode == NULL)
return;
currentSum += pTreeNode->m_nValue;
path.push_back(pTreeNode->m_nValue);
bool isLeaf = (!pTreeNode->m_pLeft && !pTreeNode->m_pRight);
if (currentSum == expectedSum && isLeaf)
{
vector<int>::iterator iter = path.begin();
for (; iter != path.end(); ++iter)
cout << *iter << '\t';
cout << endl;
}
if (pTreeNode->m_pLeft)
FindPath(pTreeNode->m_pLeft, expectedSum, path, currentSum);
if (pTreeNode->m_pRight)
FindPath(pTreeNode->m_pRight, expectedSum, path, currentSum);
currentSum -= pTreeNode->m_nValue;
path.pop_back();
}