把二叉树打印成多行

题目描述

代码

/*
struct TreeNode {
int val;
struct TreeNode *left;
struct TreeNode *right;
TreeNode(int x) :
val(x), left(NULL), right(NULL) {
}
};
*/
class Solution {
public:
vector<vector<int> > Print(TreeNode* pRoot) {
vector<vector<int> > ans;
if (pRoot != NULL) {
vector<int> vet;
queue<TreeNode*> que;

que.push(pRoot);
que.push(NULL);

TreeNode* cur;
while (!que.empty()) {
cur = que.front();
que.pop();
if (cur == NULL) {
ans.push_back(vet);
vet.clear();
if (!que.empty()) {
que.push(NULL);
}
} else {
vet.push_back(cur->val);
if (cur->left != NULL) {
que.push(cur->left);
}
if (cur->right != NULL) {
que.push(cur->right);
}
}
}

}
return ans;
}

};