1008 added.

liuyubobobo · liuyubobobo · commit 67d05ebb1810 · 2019-03-09T21:34:00.000-08:00
diff --git a/1008-Construct-Binary-Search-Tree-from-Preorder-Traversal/cpp-1008/CMakeLists.txt b/1008-Construct-Binary-Search-Tree-from-Preorder-Traversal/cpp-1008/CMakeLists.txt
@@ -0,0 +1,6 @@
+cmake_minimum_required(VERSION 3.13)
+project(D)
+
+set(CMAKE_CXX_STANDARD 14)
+
+add_executable(D main.cpp)
diff --git a/1008-Construct-Binary-Search-Tree-from-Preorder-Traversal/cpp-1008/main.cpp b/1008-Construct-Binary-Search-Tree-from-Preorder-Traversal/cpp-1008/main.cpp
@@ -0,0 +1,52 @@
+/// Source : https://leetcode.com/problems/construct-binary-search-tree-from-preorder-traversal/
+/// Author : liuyubobobo
+/// Time   : 2019-03-09
+
+#include <iostream>
+#include <vector>
+
+using namespace std;
+
+
+/// Definition for a binary tree node.
+struct TreeNode {
+    int val;
+    TreeNode *left;
+    TreeNode *right;
+    TreeNode(int x) : val(x), left(NULL), right(NULL) {}
+};
+
+
+/// Recursive
+/// Time Complexity: O(n^2)
+/// Space Complexity: O(1)
+class Solution {
+public:
+    TreeNode* bstFromPreorder(vector<int>& preorder) {
+
+        int n = preorder.size();
+        return dfs(preorder, 0, n - 1);
+    }
+
+private:
+    TreeNode* dfs(const vector<int>& v, int l, int r){
+
+        if(l > r || l >= v.size() || r >= v.size()) return NULL;
+
+        TreeNode* root = new TreeNode(v[l]);
+
+        int i;
+        for(i = l + 1; i <= r; i ++)
+            if(v[i] > v[l]) break;
+
+        root->left = dfs(v, l + 1, i - 1);
+        root->right = dfs(v, i, r);
+        return root;
+    }
+};
+
+
+int main() {
+
+    return 0;
+}
diff --git a/readme.md b/readme.md
@@ -674,4 +674,6 @@ email: [liuyubobobo@gmail.com](mailto:liuyubobobo@gmail.com)
 | 1005 | [Maximize Sum Of Array After K Negations](https://leetcode.com/problems/maximize-sum-of-array-after-k-negations/) | [无] | [C++](1005-Maximize-Sum-Of-Array-After-K-Negations/cpp-1005/) | | |
 | 1006 | [Clumsy Factorial](https://leetcode.com/problems/clumsy-factorial/) | [无] | [C++](1006-Clumsy-Factorial/cpp-1006/) | | |
 | 1007 | [Minimum Domino Rotations For Equal Row](https://leetcode.com/problems/minimum-domino-rotations-for-equal-row/) | [无] | [C++](1007-Minimum-Domino-Rotations-For-Equal-Row/cpp-1007/) | | |
+| 1008 | [Construct Binary Search Tree from Preorder Traversal](https://leetcode.com/problems/construct-binary-search-tree-from-preorder-traversal/) | [无] | [C
+++](1008-Construct-Binary-Search-Tree-from-Preorder-Traversal/cpp-1008/) | | |
 | | | | | | |
