标签：des style blog color io os ar for sp
Given a binary tree, return the preorder traversal of its nodes‘ values.
For example:
Given binary tree {1,#,2,3},
1
2
/
3
return [1,2,3].
c++版：
/** * Definition for binary tree * struct TreeNode { * int val; * TreeNode *left; * TreeNode *right; * TreeNode(int x) : val(x), left(NULL), right(NULL) {} * }; */ class Solution { public: vector<int> preorderTraversal(TreeNode *root) { // IMPORTANT: Please reset any member data you declared, as // the same Solution instance will be reused for each test case. vector<int> result; vector<int> left; vector<int> right; if(root == NULL) return result; result.push_back(root->val); left = preorderTraversal(root->left); right = preorderTraversal(root->right); if(left.size() != 0) result.insert(result.end(), left.begin(), left.end()); if(right.size() != 0) result.insert(result.end(), right.begin(), right.end()); return result; } };
Given a binary tree, return the postorder traversal of its nodes‘ values.
For example:
Given binary tree {1,#,2,3},
1
2
/
3
return [3,2,1].
C++版本：
/**
* Definition for binary tree
* struct TreeNode {
* int val;
* TreeNode *left;
* TreeNode *right;
* TreeNode(int x) : val(x), left(NULL), right(NULL) {}
* };
*/
class Solution {
public:
vector<int> postorderTraversal(TreeNode *root) {
vector<int> ret;
dfs(root, ret);
return ret;
}
void dfs(TreeNode* root, vector<int>& ret)
{
if(NULL == root)
return ;
dfs(root->left, ret);
dfs(root->right, ret);
ret.push_back(root->val);
}
};
Binary Tree Preorder Traversal and Binary Tree Postorder Traversal
标签：des style blog color io os ar for sp
原文地址：http://www.cnblogs.com/zlz-ling/p/4035509.html
