打印二叉树：不正确的叶子和空格输出

Question

我的二叉树输出有问题。我为树的打印设计的代码，其中元素的长度为1个字符，在我的树元素中是单词（最多10个字符）。请告诉我，我应该将代码中的哪些内容更改为正确的树输出。

我的代码：

int maxHeight(Node *p) {
    if (!p) return 0;
    int leftHeight = maxHeight(p->left);
    int rightHeight = maxHeight(p->right);
    return (leftHeight > rightHeight) ? leftHeight + 1 : rightHeight + 1;
}

void printBranches(int branchLen, int nodeSpaceLen, int startLen, int nodesInThisLevel, const deque<Node*>& nodesQueue) {
    deque<Node*>::const_iterator iter = nodesQueue.begin();
    for (int i = 0; i < nodesInThisLevel / 2; i++) {
        cout << ((i == 0) ? setw(startLen - 1) : setw(nodeSpaceLen - 2)) << "" << ((*iter++) ? "/" : " ");
        cout << setw(2 * branchLen + 2) << "" << ((*iter++) ? "\\" : " ");
    }
    cout << endl;
}

void printNodes(int branchLen, int nodeSpaceLen, int startLen, int nodesInThisLevel, const deque<Node*>& nodesQueue) {
    deque<Node*>::const_iterator iter = nodesQueue.begin();
    for (int i = 0; i < nodesInThisLevel; i++, iter++) {
        cout << ((i == 0) ? setw(startLen) : setw(nodeSpaceLen)) << "" << ((*iter && (*iter)->left) ? setfill('_') : setfill(' '));
        cout << setw(branchLen + 2);
        if (*iter)
            cout << (*iter)->data << "(" << (*iter)->frequency << ")";
        else
            cout << "";
        cout << ((*iter && (*iter)->right) ? setfill('_') : setfill(' ')) << setw(branchLen) << "" << setfill(' ');
    }
    cout << endl;
}

void printLeaves(int indentSpace, int level, int nodesInThisLevel, const deque<Node*>& nodesQueue) {
    deque<Node*>::const_iterator iter = nodesQueue.begin();
    for (int i = 0; i < nodesInThisLevel; i++, iter++) {
        cout << ((i == 0) ? setw(indentSpace + 2) : setw(2 * level + 2));
        if (*iter)
            cout << (*iter)->data << "(" << (*iter)->frequency << ")";
        else
            cout << "";
    }
    cout << endl;
}

void printPretty(Node *root, int level, int indentSpace) {
    int h = maxHeight(root);
    int nodesInThisLevel = 1;

    int branchLen = 2 * ((int)pow(2.0, h) - 1) - (3 - level)*(int)pow(2.0, h - 1); 
    int nodeSpaceLen = 2 + (level + 1)*(int)pow(2.0, h);  
    int startLen = branchLen + (3 - level) + indentSpace;  

    deque<Node*> nodesQueue;
    nodesQueue.push_back(root);
    for (int r = 1; r < h; r++) {
        printBranches(branchLen, nodeSpaceLen, startLen, nodesInThisLevel, nodesQueue);
        branchLen = branchLen / 2 - 1;
        nodeSpaceLen = nodeSpaceLen / 2 + 1;
        startLen = branchLen + (3 - level) + indentSpace;
        printNodes(branchLen, nodeSpaceLen, startLen, nodesInThisLevel, nodesQueue);

        for (int i = 0; i < nodesInThisLevel; i++) {
            Node *currNode = nodesQueue.front();
            nodesQueue.pop_front();
            if (currNode) {
                nodesQueue.push_back(currNode->left);
                nodesQueue.push_back(currNode->right);
            }
            else {
                nodesQueue.push_back(NULL);
                nodesQueue.push_back(NULL);
            }
        }
        nodesInThisLevel *= 2;
    }
    printBranches(branchLen, nodeSpaceLen, startLen, nodesInThisLevel, nodesQueue);
    printLeaves(indentSpace, level, nodesInThisLevel, nodesQueue);
}

如你所见，字符“\”和叶子向左移动了3个位置 http://i.stack.imgur.com/ADdGZ.png