二叉树层次遍历

c.push_back(X) 将元素X加入到c容器的最后一位

struct BTNode_s{

    int value;

    BTNode_s* pLeft;

    BTNode_s* pRight;

}BTNode;

void BFS(BTNode* pRoot)

{

    if(pRoot ==NULL)

    return;

    std::deque treeDeque;

    treeDeque.push_back(pRoot);

    while(!treeDeque.empty())

    {

        BTNode* pNode =treeDeque.front();

       printf("%d\t", pNode->value);

        if(pNode->pLeft!= NULL){

            treeDeque.push_back(pNode->pLeft);

        }

        if(pNode->pRight!= NULL){

            treeDeque.push_back(pNode->pRight);

        }

    }

}