vault backup: 2022-07-10 08:29:59

OJ notes/OJ-index.md

@@ -32,6 +32,7 @@ tag:#CS_list_need_practicing
 - [ ] [[$filename]]
 ```
  
+- [ ] [[Leetcode Binary-Search]]
 - [ ] [[Leetcode Binary-Tree-Postorder-Traversal]]
 - [ ] [[Leetcode Reverse-Linked-List]]
 - [ ] [[Leetcode Validate-Binary-Search-Tree]]
@@ -49,10 +50,12 @@ tag:#leetcode
  
 - [[Leetcode Valid-Parentheses]]
 - [[Leetcode Best-Time-To-Buy-And-Sell-Stock]]
+- [[Leetcode Binary-Search]]
 - [[Leetcode Binary-Tree-Inorder-Traversal]]
 - [[Leetcode Binary-Tree-Level-Order-Traversal]]
 - [[Leetcode Binary-Tree-Postorder-Traversal]]
 - [[Leetcode Binary-Tree-Preorder-Traversal]]
+- [[Leetcode First-Bad-Version]]
 - [[Leetcode First-Unique-Character-In-a-String]]
 - [[Leetcode Implement-Queue-Using-Stacks]]
 - [[Leetcode Insert-Into-a-Binary-Search-Tree]]
@@ -74,6 +77,7 @@ tag:#leetcode
 - [[Leetcode Reverse-Linked-List]]
 - [[Leetcode Search-a-2D-Matrix]]
 - [[Leetcode Search-In-a-Binary-Tree]]
+- [[Leetcode Search-Insert-Position]]
 - [[Leetcode Symmetric-Tree]]
 - [[Leetcode Two-Sum]]
 - [[Leetcode Two-Sum-IV-Input-Is-a-BST]]
@@ -105,10 +109,12 @@ tag:#DS tag:#coding_problem -tag:#template_remove_me
  
 - [[Leetcode Valid-Parentheses]]
 - [[Leetcode Best-Time-To-Buy-And-Sell-Stock]]
+- [[Leetcode Binary-Search]]
 - [[Leetcode Binary-Tree-Inorder-Traversal]]
 - [[Leetcode Binary-Tree-Level-Order-Traversal]]
 - [[Leetcode Binary-Tree-Postorder-Traversal]]
 - [[Leetcode Binary-Tree-Preorder-Traversal]]
+- [[Leetcode First-Bad-Version]]
 - [[Leetcode First-Unique-Character-In-a-String]]
 - [[Leetcode Implement-Queue-Using-Stacks]]
 - [[Leetcode Insert-Into-a-Binary-Search-Tree]]
@@ -129,6 +135,7 @@ tag:#DS tag:#coding_problem -tag:#template_remove_me
 - [[Leetcode Reverse-Linked-List]]
 - [[Leetcode Search-a-2D-Matrix]]
 - [[Leetcode Search-In-a-Binary-Tree]]
+- [[Leetcode Search-Insert-Position]]
 - [[Leetcode Symmetric-Tree]]
 - [[Leetcode Two-Sum]]
 - [[Leetcode Two-Sum-IV-Input-Is-a-BST]]
@@ -160,10 +167,12 @@ tag:#algorithm tag:#coding_problem -tag:#template_remove_me
 ```
  
 - [[Leetcode Best-Time-To-Buy-And-Sell-Stock]]
+- [[Leetcode Binary-Search]]
 - [[Leetcode Binary-Tree-Inorder-Traversal]]
 - [[Leetcode Binary-Tree-Level-Order-Traversal]]
 - [[Leetcode Binary-Tree-Postorder-Traversal]]
 - [[Leetcode Binary-Tree-Preorder-Traversal]]
+- [[Leetcode First-Bad-Version]]
 - [[Leetcode First-Unique-Character-In-a-String]]
 - [[Leetcode Insert-Into-a-Binary-Search-Tree]]
 - [[Leetcode Intersection-of-Two-Arrays-II]]
@@ -181,6 +190,7 @@ tag:#algorithm tag:#coding_problem -tag:#template_remove_me
 - [[Leetcode Reverse-Linked-List]]
 - [[Leetcode Search-a-2D-Matrix]]
 - [[Leetcode Search-In-a-Binary-Tree]]
+- [[Leetcode Search-Insert-Position]]
 - [[Leetcode Symmetric-Tree]]
 - [[Leetcode Two-Sum]]
 - [[Leetcode Two-Sum-IV-Input-Is-a-BST]]

OJ notes/pages/Binary Search Algorithm.md

@@ -14,7 +14,12 @@ ___
 tag:#coding_problem tag:#binary_search -tag:#template_remove_me 
 ```
  
+- [[Leetcode Binary-Search]]
+- [[Leetcode First-Bad-Version]]
+- [[Leetcode Lowest-Common-Ancestor-Of-a-Binary-Search-Tree]]
 - [[Leetcode Search-a-2D-Matrix]]
+- [[Leetcode Search-Insert-Position]]
+- [[Leetcode Two-Sum-IV-Input-Is-a-BST]]
  
 
 ##### Links:

OJ notes/pages/Leetcode Best-Time-To-Buy-And-Sell-Stock.md

@@ -15,6 +15,7 @@ tag:#Kadane_s_algorithm
 ```
  
 - [[Kadane's Algorithm]]
+- [[Leetcode Maximum-Difference-Between-Increasing-Elements]]
 - [[Leetcode Maxinum-subarray]]
  
 

OJ notes/pages/Leetcode Binary-Search.md

@@ -19,8 +19,10 @@ tag:#binary_search
 ```
  
 - [[Binary Search Algorithm]]
+- [[Leetcode First-Bad-Version]]
 - [[Leetcode Lowest-Common-Ancestor-Of-a-Binary-Search-Tree]]
 - [[Leetcode Search-a-2D-Matrix]]
+- [[Leetcode Search-Insert-Position]]
 - [[Leetcode Two-Sum-IV-Input-Is-a-BST]]
  
 

OJ notes/pages/Leetcode Binary-Tree-Inorder-Traversal.md

@@ -22,6 +22,7 @@ tag:#DFS
 - [[Leetcode Binary-Tree-Preorder-Traversal]]
 - [[Leetcode Insert-Into-a-Binary-Search-Tree]]
 - [[Leetcode Invert-Binary-Tree]]
+- [[Leetcode Lowest-Common-Ancestor-Of-a-Binary-Search-Tree]]
 - [[Leetcode Maximum-Depth-Of-Binary-Tree]]
 - [[Leetcode Path-Sum]]
 - [[Leetcode Search-In-a-Binary-Tree]]

OJ notes/pages/Leetcode Binary-Tree-Level-Order-Traversal.md

@@ -18,6 +18,7 @@
 tag:#BFS
 ```
  
+- [[Breadth First Search]]
 - [[Leetcode Maximum-Depth-Of-Binary-Tree]]
 - [[Leetcode Search-In-a-Binary-Tree]]
 - [[Leetcode Symmetric-Tree]]

OJ notes/pages/Leetcode Binary-Tree-Postorder-Traversal.md

@@ -22,6 +22,7 @@ tag:#DFS
 - [[Leetcode Binary-Tree-Preorder-Traversal]]
 - [[Leetcode Insert-Into-a-Binary-Search-Tree]]
 - [[Leetcode Invert-Binary-Tree]]
+- [[Leetcode Lowest-Common-Ancestor-Of-a-Binary-Search-Tree]]
 - [[Leetcode Maximum-Depth-Of-Binary-Tree]]
 - [[Leetcode Path-Sum]]
 - [[Leetcode Search-In-a-Binary-Tree]]

OJ notes/pages/Leetcode Binary-Tree-Preorder-Traversal.md

@@ -22,6 +22,7 @@ tag:#DFS
 - [[Leetcode Binary-Tree-Postorder-Traversal]]
 - [[Leetcode Insert-Into-a-Binary-Search-Tree]]
 - [[Leetcode Invert-Binary-Tree]]
+- [[Leetcode Lowest-Common-Ancestor-Of-a-Binary-Search-Tree]]
 - [[Leetcode Maximum-Depth-Of-Binary-Tree]]
 - [[Leetcode Path-Sum]]
 - [[Leetcode Search-In-a-Binary-Tree]]

OJ notes/pages/Leetcode First-Bad-Version.md

@@ -18,6 +18,12 @@
 tag:#binary_search
 ```
  
+- [[Binary Search Algorithm]]
+- [[Leetcode Binary-Search]]
+- [[Leetcode Lowest-Common-Ancestor-Of-a-Binary-Search-Tree]]
+- [[Leetcode Search-a-2D-Matrix]]
+- [[Leetcode Search-Insert-Position]]
+- [[Leetcode Two-Sum-IV-Input-Is-a-BST]]
  
 
 ##### Links:

OJ notes/pages/Leetcode First-Unique-Character-In-a-String.md

@@ -16,6 +16,8 @@ tag:#string OR tag:#hash_table
  
 - [[cpp_std_unordered_map]]
 - [[Leetcode Ransom-Note]]
+- [[Leetcode Two-Sum-IV-Input-Is-a-BST]]
+- [[Leetcode Valid-Anagram]]
  
 
 ##### Links:

OJ notes/pages/Leetcode Insert-Into-a-Binary-Search-Tree.md

@@ -22,6 +22,7 @@ tag:#DFS
 - [[Leetcode Binary-Tree-Postorder-Traversal]]
 - [[Leetcode Binary-Tree-Preorder-Traversal]]
 - [[Leetcode Invert-Binary-Tree]]
+- [[Leetcode Lowest-Common-Ancestor-Of-a-Binary-Search-Tree]]
 - [[Leetcode Maximum-Depth-Of-Binary-Tree]]
 - [[Leetcode Path-Sum]]
 - [[Leetcode Search-In-a-Binary-Tree]]

OJ notes/pages/Leetcode Intersection-of-Two-Arrays-II.md

@@ -18,7 +18,9 @@ tag:#unordered_map OR tag:#two_pointers OR tag:#sort
 - [[cpp_std_sort]]
 - [[cpp_std_unordered_map]]
 - [[Leetcode Merge-Sorted-Array]]
+- [[Leetcode Merge-Two-Sorted-Lists]]
 - [[Leetcode Two-Sum]]
+- [[Two pointers approach]]
  
 
 

OJ notes/pages/Leetcode Invert-Binary-Tree.md

@@ -18,6 +18,7 @@
 tag:#recursion tag:#DFS
 ```
  
+- [[Leetcode Insert-Into-a-Binary-Search-Tree]]
 - [[Leetcode Path-Sum]]
 - [[Leetcode Symmetric-Tree]]
  

OJ notes/pages/Leetcode Maximum-Depth-Of-Binary-Tree.md

@@ -18,6 +18,7 @@
 tag:#BFS
 ```
  
+- [[Breadth First Search]]
 - [[Leetcode Binary-Tree-Level-Order-Traversal]]
 - [[Leetcode Search-In-a-Binary-Tree]]
 - [[Leetcode Symmetric-Tree]]

OJ notes/pages/Leetcode Maxinum-subarray.md

@@ -19,6 +19,7 @@ tag:#Kadane_s_algorithm
  
 - [[Kadane's Algorithm]]
 - [[Leetcode Best-Time-To-Buy-And-Sell-Stock]]
+- [[Leetcode Maximum-Difference-Between-Increasing-Elements]]
  
 
 

OJ notes/pages/Leetcode Merge-Sorted-Array.md

@@ -14,9 +14,15 @@
 tag:#set OR tag:#multiset OR tag:#merge_sort OR tag:#vector OR tag:#two_pointers
 ```
  
+- [[Binary Search Algorithm]]
 - [[cpp_Range_based_for_loop]]
 - [[cpp_std_multiset]]
 - [[Leetcode Intersection-of-Two-Arrays-II]]
+- [[Leetcode Merge-Two-Sorted-Lists]]
+- [[Leetcode Reshape-The-Matrix]]
+- [[Leetcode Search-a-2D-Matrix]]
+- [[Leetcode Valid-Sudoku]]
+- [[Two pointers approach]]
  
 
 

OJ notes/pages/Leetcode Merge-Two-Sorted-Lists.md

@@ -16,6 +16,7 @@ tag:#two_pointers
  
 - [[Leetcode Intersection-of-Two-Arrays-II]]
 - [[Leetcode Merge-Sorted-Array]]
+- [[Two pointers approach]]
  
 
 ##### Links:

OJ notes/pages/Leetcode Pascal's-Triangle.md

@@ -14,9 +14,22 @@
 tag:#recursion OR tag:#iteration OR tag:#array -tag:#Kadane_s_algorithm 
 ```
  
+- [[Binary Search Algorithm]]
 - [[cpp_Range_based_for_loop]]
+- [[Leetcode Binary-Search]]
+- [[Leetcode First-Bad-Version]]
+- [[Leetcode First-Unique-Character-In-a-String]]
+- [[Leetcode Insert-Into-a-Binary-Search-Tree]]
+- [[Leetcode Invert-Binary-Tree]]
+- [[Leetcode Path-Sum]]
+- [[Leetcode Ransom-Note]]
 - [[Leetcode Reshape-The-Matrix]]
+- [[Leetcode Reverse-Linked-List]]
+- [[Leetcode Search-Insert-Position]]
+- [[Leetcode Symmetric-Tree]]
 - [[Leetcode Two-Sum]]
+- [[Leetcode Valid-Anagram]]
+- [[Two pointers approach]]
  
 
 

OJ notes/pages/Leetcode Path-Sum.md

@@ -23,6 +23,7 @@ tag:#DFS
 - [[Leetcode Binary-Tree-Preorder-Traversal]]
 - [[Leetcode Insert-Into-a-Binary-Search-Tree]]
 - [[Leetcode Invert-Binary-Tree]]
+- [[Leetcode Lowest-Common-Ancestor-Of-a-Binary-Search-Tree]]
 - [[Leetcode Maximum-Depth-Of-Binary-Tree]]
 - [[Leetcode Search-In-a-Binary-Tree]]
 - [[Leetcode Symmetric-Tree]]

OJ notes/pages/Leetcode Ransom-Note.md

@@ -16,6 +16,8 @@ tag:#hash_table
  
 - [[cpp_std_unordered_map]]
 - [[Leetcode First-Unique-Character-In-a-String]]
+- [[Leetcode Two-Sum-IV-Input-Is-a-BST]]
+- [[Leetcode Valid-Anagram]]
  
 
 ##### Links:

OJ notes/pages/Leetcode Reshape-The-Matrix.md

@@ -12,11 +12,20 @@
 (tag:#array OR tag:#vector) -tag:#Kadane_s_algorithm 
 ```
  
+- [[Binary Search Algorithm]]
 - [[cpp_Range_based_for_loop]]
+- [[Leetcode Binary-Search]]
+- [[Leetcode First-Bad-Version]]
+- [[Leetcode First-Unique-Character-In-a-String]]
 - [[Leetcode Merge-Sorted-Array]]
 - [[Leetcode Pascal's-Triangle]]
+- [[Leetcode Ransom-Note]]
+- [[Leetcode Search-a-2D-Matrix]]
+- [[Leetcode Search-Insert-Position]]
 - [[Leetcode Two-Sum]]
+- [[Leetcode Valid-Anagram]]
 - [[Leetcode Valid-Sudoku]]
+- [[Two pointers approach]]
  
 
 

OJ notes/pages/Leetcode Search-In-a-Binary-Tree.md

@@ -18,12 +18,14 @@
 tag:#DFS OR tag:#BFS
 ```
  
+- [[Breadth First Search]]
 - [[Leetcode Binary-Tree-Inorder-Traversal]]
 - [[Leetcode Binary-Tree-Level-Order-Traversal]]
 - [[Leetcode Binary-Tree-Postorder-Traversal]]
 - [[Leetcode Binary-Tree-Preorder-Traversal]]
 - [[Leetcode Insert-Into-a-Binary-Search-Tree]]
 - [[Leetcode Invert-Binary-Tree]]
+- [[Leetcode Lowest-Common-Ancestor-Of-a-Binary-Search-Tree]]
 - [[Leetcode Maximum-Depth-Of-Binary-Tree]]
 - [[Leetcode Path-Sum]]
 - [[Leetcode Symmetric-Tree]]

OJ notes/pages/Leetcode Search-Insert-Position.md

@@ -0,0 +1,103 @@
+# Leetcode Search-Insert-Position
+
+#### 2022-07-09 10:25
+
+> ##### Algorithms:
+> #algorithm #binary_search 
+> ##### Data structures:
+> #DS #array 
+> ##### Difficulty:
+> #coding_problem #difficulty-easy 
+> ##### Additional tags:
+> #leetcode
+> ##### Revisions:
+> N/A
+
+##### Related topics:
+```expander
+tag:#binary_search
+```
+ 
+- [[Binary Search Algorithm]]
+- [[Leetcode Binary-Search]]
+- [[Leetcode First-Bad-Version]]
+- [[Leetcode Lowest-Common-Ancestor-Of-a-Binary-Search-Tree]]
+- [[Leetcode Search-a-2D-Matrix]]
+- [[Leetcode Two-Sum-IV-Input-Is-a-BST]]
+ 
+
+##### Links:
+- [Link to problem](https://leetcode.com/problems/binary-search/)
+___
+### Problem
+
+Given an array of integers `nums` which is sorted in ascending order, and an integer `target`, write a function to search `target` in `nums`. If `target` exists, then return its index. Otherwise, return `-1`.
+
+You must write an algorithm with `O(log n)` runtime complexity.
+
+#### Examples
+
+**Example 1:**
+
+**Input:** nums = [-1,0,3,5,9,12], target = 9
+**Output:** 4
+**Explanation:** 9 exists in nums and its index is 4
+
+**Example 2:**
+
+**Input:** nums = [-1,0,3,5,9,12], target = 2
+**Output:** -1
+**Explanation:** 2 does not exist in nums so return -1
+
+#### Constraints
+
+-   `1 <= nums.length <= 104`
+-   `-104 < nums[i], target < 104`
+-   All the integers in `nums` are **unique**.
+-   `nums` is sorted in ascending order.
+
+### Thoughts
+
+> [!summary]
+> This is a #binary_search problem.
+
+similar to [[Leetcode First-Bad-Version]], this relies on the converging nature of Bi-search
+
+if the value is found, simply return it
+
+if not found, at the end, position `l - 1` should be smaller than val.
+
+and position `l` should be bigger, which is the position for the answer:
+```
+If not, return the index where it would be if it were inserted in order.
+```
+
+### Solution
+
+Iteration
+```cpp
+class Solution {
+public:
+  int searchInsert(vector<int>& nums, int target) {
+    // variant of bi-search
+    int r = nums.size() - 1;
+    int l = 0;
+    int mid, val;
+    
+    do {
+      mid = l + (r - l) / 2;
+      val = nums[mid];
+      
+      if (val == target) {
+        return mid;
+      } else if (val < target) {
+        l = mid + 1;
+      } else {
+        r = mid - 1;
+      }
+    } while (l <= r);
+    
+    return l;
+  }
+};
+```

OJ notes/pages/Leetcode Search-a-2D-Matrix.md

@@ -16,8 +16,13 @@ tag:#vector OR tag:#vector_2d OR tag:#binary_search
  
 - [[Binary Search Algorithm]]
 - [[cpp_Range_based_for_loop]]
+- [[Leetcode Binary-Search]]
+- [[Leetcode First-Bad-Version]]
+- [[Leetcode Lowest-Common-Ancestor-Of-a-Binary-Search-Tree]]
 - [[Leetcode Merge-Sorted-Array]]
 - [[Leetcode Reshape-The-Matrix]]
+- [[Leetcode Search-Insert-Position]]
+- [[Leetcode Two-Sum-IV-Input-Is-a-BST]]
 - [[Leetcode Valid-Sudoku]]
  
 

OJ notes/pages/Leetcode Symmetric-Tree.md

@@ -18,12 +18,14 @@
 tag:#DFS OR tag:#BFS
 ```
  
+- [[Breadth First Search]]
 - [[Leetcode Binary-Tree-Inorder-Traversal]]
 - [[Leetcode Binary-Tree-Level-Order-Traversal]]
 - [[Leetcode Binary-Tree-Postorder-Traversal]]
 - [[Leetcode Binary-Tree-Preorder-Traversal]]
 - [[Leetcode Insert-Into-a-Binary-Search-Tree]]
 - [[Leetcode Invert-Binary-Tree]]
+- [[Leetcode Lowest-Common-Ancestor-Of-a-Binary-Search-Tree]]
 - [[Leetcode Maximum-Depth-Of-Binary-Tree]]
 - [[Leetcode Path-Sum]]
 - [[Leetcode Search-In-a-Binary-Tree]]

OJ notes/pages/Leetcode Two-Sum-IV-Input-Is-a-BST.md

@@ -19,10 +19,15 @@ tag:#BFS OR tag:#binary_search
 ```
  
 - [[Binary Search Algorithm]]
+- [[Breadth First Search]]
+- [[Leetcode Binary-Search]]
 - [[Leetcode Binary-Tree-Level-Order-Traversal]]
+- [[Leetcode First-Bad-Version]]
+- [[Leetcode Lowest-Common-Ancestor-Of-a-Binary-Search-Tree]]
 - [[Leetcode Maximum-Depth-Of-Binary-Tree]]
 - [[Leetcode Search-a-2D-Matrix]]
 - [[Leetcode Search-In-a-Binary-Tree]]
+- [[Leetcode Search-Insert-Position]]
 - [[Leetcode Symmetric-Tree]]
  
 

OJ notes/pages/Leetcode Valid-Sudoku.md

@@ -12,9 +12,11 @@
 tag:#vector
 ```
  
+- [[Binary Search Algorithm]]
 - [[cpp_Range_based_for_loop]]
 - [[Leetcode Merge-Sorted-Array]]
 - [[Leetcode Reshape-The-Matrix]]
+- [[Leetcode Search-a-2D-Matrix]]
  
 
 ##### Links:

OJ notes/pages/cpp_Range_based_for_loop.md

@@ -13,6 +13,8 @@ tag:#coding_problem tag:#array tag:#vector tag:#multiset -tag:#template_remove_m
 ```
  
  
+
+
 ##### Links:
 - [cppreference](https://en.cppreference.com/w/cpp/language/range-for)
 ___