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2
.obsidian/appearance.json vendored
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{ {
"theme": "moonstone", "theme": "obsidian",
"translucency": true, "translucency": true,
"cssTheme": "Prism", "cssTheme": "Prism",
"interfaceFontFamily": "IBM Plex Sans", "interfaceFontFamily": "IBM Plex Sans",

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.obsidian/graph.json vendored
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} }
], ],
"collapse-display": false, "collapse-display": false,
"showArrow": false, "showArrow": true,
"textFadeMultiplier": 0, "textFadeMultiplier": 0,
"nodeSizeMultiplier": 1, "nodeSizeMultiplier": 1,
"lineSizeMultiplier": 1, "lineSizeMultiplier": 1,
"collapse-forces": false, "collapse-forces": false,
"centerStrength": 0.518713248970312, "centerStrength": 0.5,
"repelStrength": 10, "repelStrength": 10.5952380952381,
"linkStrength": 1, "linkStrength": 0.505952380952381,
"linkDistance": 250, "linkDistance": 259,
"scale": 0.9747267101258579, "scale": 0.34081054256054544,
"close": true "close": false
} }

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OJ notes/pages/Binary Search Algorithm.md
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##### Difficulty: ##### Difficulty:
#CS_analysis #difficulty-easy #CS_analysis #difficulty_easy
##### Related problems: ##### Related problems:

2
OJ notes/pages/Bit-Manipulation count true trick.md
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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #CS_analysis #difficulty-easy > #CS_analysis #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:

2
OJ notes/pages/Breadth First Search.md
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@ -12,7 +12,7 @@
> >
> ##### Difficulty: > ##### Difficulty:
> >
> #CS_analysis #difficulty- > #CS_analysis #difficulty_
> >
> ##### Additional tags: > ##### Additional tags:

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OJ notes/pages/Floyd's Cycle Finding Algorithm.md
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@ -14,7 +14,7 @@
##### Difficulty: ##### Difficulty:
#CS_analysis #difficulty-easy #CS_analysis #difficulty_easy
##### Related problems: ##### Related problems:

2
OJ notes/pages/Kadane's Algorithm.md
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@ -14,7 +14,7 @@
##### Difficulty: ##### Difficulty:
#CS_analysis #difficulty-easy #CS_analysis #difficulty_easy
##### Time complexity: ##### Time complexity:

2
OJ notes/pages/Leetcode 01-Matrix.md
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@ -12,7 +12,7 @@
> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-medium > #coding_problem #difficulty_medium
> >
> ##### Additional tags: > ##### Additional tags:
> >

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OJ notes/pages/Leetcode Add-Strings.md
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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >
@ -49,9 +49,9 @@ You must solve the problem without using any built-in library for handling large
#### Constraints #### Constraints
- `1 <= num1.length, num2.length <= 104` - `1 <= num1.length, num2.length <= 104`
- `num1` and `num2` consist of only digits. - `num1` and `num2` consist of only digits.
- `num1` and `num2` don't have any leading zeros except for the zero itself. - `num1` and `num2` don't have any leading zeros except for the zero itself.
### Thoughts ### Thoughts

2
OJ notes/pages/Leetcode Average-Salary-Excluding-the-Minimum-and-Maximum-Salary.md
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@ -4,7 +4,7 @@
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >

2
OJ notes/pages/Leetcode Best-Time-To-Buy-And-Sell-Stock.md
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@ -14,7 +14,7 @@
##### Difficulty: ##### Difficulty:
#leetcode #coding_problem #difficulty-easy #leetcode #coding_problem #difficulty_easy
##### Related topics: ##### Related topics:

2
OJ notes/pages/Leetcode Binary-Search.md
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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >

2
OJ notes/pages/Leetcode Binary-Tree-Inorder-Traversal.md
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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >

2
OJ notes/pages/Leetcode Binary-Tree-Level-Order-Traversal.md
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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-medium > #coding_problem #difficulty_medium
> >
> ##### Additional tags: > ##### Additional tags:
> >

2
OJ notes/pages/Leetcode Binary-Tree-Postorder-Traversal.md
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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty- > #coding_problem #difficulty_
> >
> ##### Additional tags: > ##### Additional tags:
> >

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OJ notes/pages/Leetcode Binary-Tree-Preorder-Traversal.md
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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >

2
OJ notes/pages/Leetcode Check-If-It-Is-a-Straight-Line.md
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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >

2
OJ notes/pages/Leetcode Climbing-Chairs.md
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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >

2
OJ notes/pages/Leetcode Combinations.md
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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-medium > #coding_problem #difficulty_medium
> >
> ##### Additional tags: > ##### Additional tags:
> >

2
OJ notes/pages/Leetcode Count-Odd-Numbers-in-an-Interval-Range.md
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@ -8,7 +8,7 @@
> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >

2
OJ notes/pages/Leetcode Design-Hash.md
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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >

2
OJ notes/pages/Leetcode First-Bad-Version.md
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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >

2
OJ notes/pages/Leetcode First-Unique-Character-In-a-String.md
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##### Difficulty: ##### Difficulty:
#leetcode #coding_problem #difficulty-easy #leetcode #coding_problem #difficulty_easy
##### Related topics: ##### Related topics:

2
OJ notes/pages/Leetcode Flood-Fill.md
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@ -12,7 +12,7 @@
> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >

10
OJ notes/pages/Leetcode Group-Anagrams.md
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@ -8,7 +8,7 @@
> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-medium > #coding_problem #difficulty_medium
> >
> ##### Additional tags: > ##### Additional tags:
> >
@ -55,9 +55,9 @@ An **Anagram** is a word or phrase formed by rearranging the letters of a differ
#### Constraints #### Constraints
- `1 <= strs.length <= 104` - `1 <= strs.length <= 104`
- `0 <= strs[i].length <= 100` - `0 <= strs[i].length <= 100`
- `strs[i]` consists of lowercase English letters. - `strs[i]` consists of lowercase English letters.
### Thoughts ### Thoughts
@ -68,6 +68,7 @@ An **Anagram** is a word or phrase formed by rearranging the letters of a differ
This one can be solved simply using two-way hash tables, This one can be solved simply using two-way hash tables,
consisting of two hash tables: consisting of two hash tables:
- ana2id: turn anagram into an id - ana2id: turn anagram into an id
- id2str: turn id into strings that has the anagrams - id2str: turn id into strings that has the anagrams
@ -76,6 +77,7 @@ CPP-style initialization of C's array.
> [!tip] > [!tip]
> CPP-style initialization of C array #tip > CPP-style initialization of C array #tip
>
> ```cpp > ```cpp
> array<int, 26> ana = {}; > array<int, 26> ana = {};
> ``` > ```

2
OJ notes/pages/Leetcode Happy-Number.md
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@ -8,7 +8,7 @@
> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >

2
OJ notes/pages/Leetcode House-Robber.md
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@ -8,7 +8,7 @@
> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-medium > #coding_problem #difficulty_medium
> >
> ##### Additional tags: > ##### Additional tags:
> >

2
OJ notes/pages/Leetcode Implement-Queue-Using-Stacks.md
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@ -8,7 +8,7 @@
> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >

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OJ notes/pages/Leetcode Increasing-Triplet-Subsequence.md
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@ -12,7 +12,7 @@
> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-medium > #coding_problem #difficulty_medium
> >
> ##### Additional tags: > ##### Additional tags:
> >
@ -55,8 +55,8 @@ Given an integer array `nums`, return `true` _if there exists a triple of indice
#### Constraints #### Constraints
- `1 <= nums.length <= 5 * 105` - `1 <= nums.length <= 5 * 105`
- `-231 <= nums[i] <= 231 - 1` - `-231 <= nums[i] <= 231 - 1`
### Thoughts ### Thoughts
@ -68,17 +68,17 @@ Use two variables: `small` and `big` to keep track of stuff.
For each element, there are three possibilities: For each element, there are three possibilities:
- the element is smaller than `small`, assign the element - the element is smaller than `small`, assign the element
to `small` to `small`
> `small` and `big` doesn't represent `i` and `j`, > `small` and `big` doesn't represent `i` and `j`,
> accurately, they get updated lazily. > accurately, they get updated lazily.
> And because we don't need to show `i`, `j`, `k`, this > And because we don't need to show `i`, `j`, `k`, this
> will be just fine > will be just fine
- the element is greater than `small`: - the element is greater than `small`:
- the element is smaller than `big`, change `big`, this - the element is smaller than `big`, change `big`, this
allows more possibilities allows more possibilities
- the element is bigger than `big`, found, exit loop. - the element is bigger than `big`, found, exit loop.
> #### Why not #stack ? > #### Why not #stack ?
> >

2
OJ notes/pages/Leetcode Insert-Into-a-Binary-Search-Tree.md
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@ -12,7 +12,7 @@
> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-medium > #coding_problem #difficulty_medium
> >
> ##### Additional tags: > ##### Additional tags:
> >

2
OJ notes/pages/Leetcode Intersection-of-Two-Arrays-II.md
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@ -16,7 +16,7 @@
##### Difficulty: ##### Difficulty:
#leetcode #coding_problem #difficulty-easy #leetcode #coding_problem #difficulty_easy
##### Related topics: ##### Related topics:

2
OJ notes/pages/Leetcode Invert-Binary-Tree.md
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@ -12,7 +12,7 @@
> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >

2
OJ notes/pages/Leetcode Largest-Perimeter-Triangle.md
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@ -8,7 +8,7 @@
> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >

2
OJ notes/pages/Leetcode Letter-Case-Combination.md
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@ -8,7 +8,7 @@
> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-medium > #coding_problem #difficulty_medium
> >
> ##### Additional tags: > ##### Additional tags:
> >

2
OJ notes/pages/Leetcode Linked-List-Cycle.md
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@ -14,7 +14,7 @@
##### Difficulty: ##### Difficulty:
#leetcode #coding_problem #difficulty-easy #leetcode #coding_problem #difficulty_easy
##### Related topics: ##### Related topics:

9
OJ notes/pages/Leetcode Longest-Palindrome.md
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@ -12,7 +12,7 @@
> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >
@ -30,7 +30,7 @@
### Problem ### Problem
Given a string `s` which consists of lowercase or uppercase letters, return _the length of the **longest palindrome**_ that can be built with those letters. Given a string `s` which consists of lowercase or uppercase letters, return *the length of the **longest palindrome*** that can be built with those letters.
Letters are **case sensitive**, for example, `"Aa"` is not considered a palindrome here. Letters are **case sensitive**, for example, `"Aa"` is not considered a palindrome here.
@ -50,8 +50,8 @@ Letters are **case sensitive**, for example, `"Aa"` is not considered a palindr
#### Constraints #### Constraints
- `1 <= s.length <= 2000` - `1 <= s.length <= 2000`
- `s` consists of lowercase **and/or** uppercase English letters only. - `s` consists of lowercase **and/or** uppercase English letters only.
### Thoughts ### Thoughts
@ -61,6 +61,7 @@ Letters are **case sensitive**, for example, `"Aa"` is not considered a palindr
The solution is simple: count the apperances, sort it using The solution is simple: count the apperances, sort it using
std::greater<int>(), and select all even number, for odd std::greater<int>(), and select all even number, for odd
number `i`: number `i`:
- if odd numbers has been used: `ans += i - 1` (make it - if odd numbers has been used: `ans += i - 1` (make it
even) even)
- if not: `ans += i`, and mark odd number used - if not: `ans += i`, and mark odd number used

2
OJ notes/pages/Leetcode Longest-Substring-Without-Repeating-Characters.md
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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-medium > #coding_problem #difficulty_medium
> >
> ##### Additional tags: > ##### Additional tags:
> >

2
OJ notes/pages/Leetcode Lowest-Common-Ancestor-Of-a-Binary-Search-Tree.md
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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >

2
OJ notes/pages/Leetcode Max-Area-of-Island.md
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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-medium > #coding_problem #difficulty_medium
> >
> ##### Additional tags: > ##### Additional tags:
> >

2
OJ notes/pages/Leetcode Maximum-Depth-Of-Binary-Tree.md
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@ -12,7 +12,7 @@
> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >

2
OJ notes/pages/Leetcode Maximum-Difference-Between-Increasing-Elements.md
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@ -8,7 +8,7 @@
> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >

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OJ notes/pages/Leetcode Maxinum-subarray.md
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@ -14,7 +14,7 @@
##### Difficulty: ##### Difficulty:
#leetcode #coding_problem #difficulty-easy #leetcode #coding_problem #difficulty_easy
##### Links: ##### Links:

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OJ notes/pages/Leetcode Merge-Intervals.md
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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-medium > #coding_problem #difficulty_medium
> >
> ##### Additional tags: > ##### Additional tags:
> >

2
OJ notes/pages/Leetcode Merge-Sorted-Array.md
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@ -14,7 +14,7 @@
##### Difficulty: ##### Difficulty:
#leetcode #coding_problem #difficulty-easy #leetcode #coding_problem #difficulty_easy
##### Related topics: ##### Related topics:

2
OJ notes/pages/Leetcode Merge-Two-Binary-Trees.md
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@ -12,7 +12,7 @@
> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >

2
OJ notes/pages/Leetcode Merge-Two-Sorted-Lists.md
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@ -14,7 +14,7 @@
##### Difficulty: ##### Difficulty:
#leetcode #coding_problem #difficulty-easy #leetcode #coding_problem #difficulty_easy
##### Related topics: ##### Related topics:

2
OJ notes/pages/Leetcode Middle-of-the-Linked-List.md
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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >

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OJ notes/pages/Leetcode Move-Zeroes.md
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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >

2
OJ notes/pages/Leetcode Next-Greater-Element-I.md
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@ -8,7 +8,7 @@
> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >

2
OJ notes/pages/Leetcode Non-Overlapping-Intervals.md
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@ -12,7 +12,7 @@
> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-medium > #coding_problem #difficulty_medium
> >
> ##### Additional tags: > ##### Additional tags:
> >

2
OJ notes/pages/Leetcode Number-of-1-Bits.md
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@ -12,7 +12,7 @@
> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >

3
OJ notes/pages/Leetcode Partition-Labels.md
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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-medium > #coding_problem #difficulty_medium
> >
> ##### Additional tags: > ##### Additional tags:
> >
@ -62,6 +62,7 @@ A partition like "ababcbacadefegde", "hijhklij" is incorrect, because it splits
#### Why is it a greedy problem? #### Why is it a greedy problem?
Consider this situation: Consider this situation:
``` ```
s: ababc s: ababc
partition: abab|c partition: abab|c

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OJ notes/pages/Leetcode Pascal's-Triangle-II.md
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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >

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OJ notes/pages/Leetcode Pascal's-Triangle.md
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##### Difficulty: ##### Difficulty:
#leetcode #coding_problem #difficulty-easy #leetcode #coding_problem #difficulty_easy
##### Related topics: ##### Related topics:

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OJ notes/pages/Leetcode Path-Sum.md
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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >

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OJ notes/pages/Leetcode Permutation-In-String.md
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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-medium > #coding_problem #difficulty_medium
> >
> ##### Additional tags: > ##### Additional tags:
> >

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OJ notes/pages/Leetcode Permutations.md
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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-medium > #coding_problem #difficulty_medium
> >
> ##### Additional tags: > ##### Additional tags:
> >

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OJ notes/pages/Leetcode Populating-Next-Right-Pointers-In-Each-Node.md
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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-medium > #coding_problem #difficulty_medium
> >
> ##### Additional tags: > ##### Additional tags:
> >

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OJ notes/pages/Leetcode Power-of-Two.md
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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-medium > #coding_problem #difficulty_medium
> >
> ##### Additional tags: > ##### Additional tags:
> >

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OJ notes/pages/Leetcode Product-of-Array-Except-Self.md
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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-medium > #coding_problem #difficulty_medium
> >
> ##### Additional tags: > ##### Additional tags:
> >
@ -25,7 +25,7 @@
##### Links: ##### Links:
- [Link to problem](https://leetcode.com/problems/product-of-array-except-self/) - [Link to problem](https://leetcode.com/problems/product-of-array-except-self/)
- [Solution with explanation](https://leetcode.com/problems/product-of-array-except-self/discuss/1597994/C%2B%2BPython-4-Simple-Solutions-w-Explanation-or-Prefix-and-Suffix-product-O(1)-space-approach) - [Solution with explanation](<https://leetcode.com/problems/product-of-array-except-self/discuss/1597994/C%2B%2BPython-4-Simple-Solutions-w-Explanation-or-Prefix-and-Suffix-product-O(1)-space-approach>)
--- ---
@ -51,9 +51,9 @@ You must write an algorithm that runs in `O(n)` time and without using the div
#### Constraints #### Constraints
- `2 <= nums.length <= 105` - `2 <= nums.length <= 105`
- `-30 <= nums[i] <= 30` - `-30 <= nums[i] <= 30`
- The product of any prefix or suffix of `nums` is **guaranteed** to fit in a **32-bit** integer. - The product of any prefix or suffix of `nums` is **guaranteed** to fit in a **32-bit** integer.
### Thoughts ### Thoughts
@ -148,6 +148,7 @@ public:
``` ```
First iteration: First iteration:
```cpp ```cpp
class Solution { class Solution {
public: public:

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@ -14,7 +14,7 @@
##### Difficulty: ##### Difficulty:
#leetcode #coding_problem #difficulty-easy #leetcode #coding_problem #difficulty_easy
##### Related topics: ##### Related topics:

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@ -8,7 +8,7 @@
> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >

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@ -10,7 +10,7 @@
##### Difficulty: ##### Difficulty:
#leetcode #coding_problem #difficulty-easy #leetcode #coding_problem #difficulty_easy
##### Related topics: ##### Related topics:

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@ -12,7 +12,7 @@
> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-medium > #coding_problem #difficulty_medium
> >
> ##### Additional tags: > ##### Additional tags:
> >

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OJ notes/pages/Leetcode Repeated-DNA-Sequences.md
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@ -8,7 +8,7 @@
> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-medium > #coding_problem #difficulty_medium
> >
> ##### Additional tags: > ##### Additional tags:
> >
@ -28,7 +28,7 @@
The **DNA sequence** is composed of a series of nucleotides abbreviated as `'A'`, `'C'`, `'G'`, and `'T'`. The **DNA sequence** is composed of a series of nucleotides abbreviated as `'A'`, `'C'`, `'G'`, and `'T'`.
- For example, `"ACGAATTCCG"` is a **DNA sequence**. - For example, `"ACGAATTCCG"` is a **DNA sequence**.
When studying **DNA**, it is useful to identify repeated sequences within the DNA. When studying **DNA**, it is useful to identify repeated sequences within the DNA.
@ -57,18 +57,21 @@ The question ask for an answer, and the substrings can
overlap. So, using a map is prefered(Why?) overlap. So, using a map is prefered(Why?)
Two reasons: Two reasons:
- Easy way to know if a array is a duplicate (set, map can - Easy way to know if a array is a duplicate (set, map can
suffice.) suffice.)
- Keep information on how many duplicates found, so we only - Keep information on how many duplicates found, so we only
append it to the answer the first time we meet it. append it to the answer the first time we meet it.
One trip-over hole: in the for loop, upper bound should be: One trip-over hole: in the for loop, upper bound should be:
```cpp ```cpp
for (int i = 0, top = s.size() - 9; i < top; i++) for (int i = 0, top = s.size() - 9; i < top; i++)
^^^ ^^^
``` ```
Minus 9, because 9 is the extended length for an subarray starting with i. Minus 9, because 9 is the extended length for an subarray starting with i.
``` ```
1234567890 1234567890
^ ^ ^ ^

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@ -10,7 +10,7 @@
##### Difficulty: ##### Difficulty:
#leetcode #coding_problem #difficulty-easy #leetcode #coding_problem #difficulty_easy
##### Related topics: ##### Related topics:

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@ -12,7 +12,7 @@
> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >

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@ -14,7 +14,7 @@
##### Difficulty: ##### Difficulty:
#leetcode #coding_problem #difficulty-medium #leetcode #coding_problem #difficulty_medium
##### Lists: ##### Lists:

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@ -12,7 +12,7 @@
> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >

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@ -12,7 +12,7 @@
> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >

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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-medium > #coding_problem #difficulty_medium
> >
> ##### Additional tags: > ##### Additional tags:
> >

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@ -12,7 +12,7 @@
> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-medium > #coding_problem #difficulty_medium
> >
> ##### Additional tags: > ##### Additional tags:
> >

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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-medium > #coding_problem #difficulty_medium
> >
> ##### Additional tags: > ##### Additional tags:
> >

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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-medium > #coding_problem #difficulty_medium
> >
> ##### Additional tags: > ##### Additional tags:
> >

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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >

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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >

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##### Difficulty: ##### Difficulty:
#leetcode #coding_problem #difficulty-easy #leetcode #coding_problem #difficulty_easy
##### Related topics: ##### Related topics:

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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >

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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-medium > #coding_problem #difficulty_medium
> >
> ##### Additional tags: > ##### Additional tags:
> >

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@ -12,7 +12,7 @@
> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >

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@ -12,7 +12,7 @@
> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-medium > #coding_problem #difficulty_medium
> >
> ##### Additional tags: > ##### Additional tags:
> >
@ -49,9 +49,9 @@ A subarray is a contiguous **non-empty** sequence of elements within an array.
#### Constraints #### Constraints
- `1 <= nums.length <= 2 * 104` - `1 <= nums.length <= 2 * 104`
- `-1000 <= nums[i] <= 1000` - `-1000 <= nums[i] <= 1000`
- `-107 <= k <= 107` - `-107 <= k <= 107`
### Thoughts ### Thoughts
@ -111,6 +111,7 @@ public:
``` ```
TLE, brute force TLE, brute force
```cpp ```cpp
class Solution { class Solution {
public: public:

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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-medium > #coding_problem #difficulty_medium
> >
> ##### Additional tags: > ##### Additional tags:
> >

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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >

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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-medium > #coding_problem #difficulty_medium
> >
> ##### Additional tags: > ##### Additional tags:
> >

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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >

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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >

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##### Difficulty: ##### Difficulty:
#coding_problem #leetcode #difficulty-easy #coding_problem #leetcode #difficulty_easy
##### Related topics: ##### Related topics:

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##### Difficulty: ##### Difficulty:
#leetcode #coding_problem #difficulty-easy #leetcode #coding_problem #difficulty_easy
##### Related topics: ##### Related topics:

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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >

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##### Difficulty: ##### Difficulty:
#leetcode #coding_problem #difficulty-easy #leetcode #coding_problem #difficulty_easy
##### Related topics: ##### Related topics:

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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-medium > #coding_problem #difficulty_medium
> >
> ##### Additional tags: > ##### Additional tags:
> >

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> >
> ##### Difficulty: > ##### Difficulty:
> >
> #coding_problem #difficulty-easy > #coding_problem #difficulty_easy
> >
> ##### Additional tags: > ##### Additional tags:
> >
@ -49,12 +49,12 @@ Here **follow** means a full match, such that there is a bijection between a let
#### Constraints #### Constraints
- `1 <= pattern.length <= 300` - `1 <= pattern.length <= 300`
- `pattern` contains only lower-case English letters. - `pattern` contains only lower-case English letters.
- `1 <= s.length <= 3000` - `1 <= s.length <= 3000`
- `s` contains only lowercase English letters and spaces `' '`. - `s` contains only lowercase English letters and spaces `' '`.
- `s` **does not contain** any leading or trailing spaces. - `s` **does not contain** any leading or trailing spaces.
- All the words in `s` are separated by a **single space**. - All the words in `s` are separated by a **single space**.
### Thoughts ### Thoughts
@ -65,6 +65,7 @@ The main part is using two hash tables, to check for
mismatches, and using `istringstream` to read from string mismatches, and using `istringstream` to read from string
Two hash tables: Two hash tables:
- One is used to check for s has one and only bound word - One is used to check for s has one and only bound word
- The other is used to check that the word is only stored - The other is used to check that the word is only stored
once once

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##### Difficulty: ##### Difficulty:
#CS_analysis #difficulty-easy #CS_analysis #difficulty_easy
##### Related problems: ##### Related problems:

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##### Difficulty: ##### Difficulty:
#CS_analysis #difficulty-easy #CS_analysis #difficulty_easy
##### Related problems: ##### Related problems:

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##### Difficulty: ##### Difficulty:
#CS_analysis #difficulty-easy #CS_analysis #difficulty_easy
##### Related problems: ##### Related problems:

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##### Difficulty: ##### Difficulty:
#CS_analysis #difficulty-easy #CS_analysis #difficulty_easy
##### Related problems: ##### Related problems: