fuck-leetcode
diff --git a/‎README.md
+36-36 b/‎README.md
+36-36
diff --git a/‎solutions/0121-best-time-to-buy-and-sell-stock.md renamed to ‎solutions/1-1000/121-best-time-to-buy-and-sell-stock.md b/‎solutions/0121-best-time-to-buy-and-sell-stock.md renamed to ‎solutions/1-1000/121-best-time-to-buy-and-sell-stock.md
diff --git a/‎solutions/0122-best-time-to-buy-and-sell-stock-ii.md renamed to ‎solutions/1-1000/122-best-time-to-buy-and-sell-stock-ii.md b/‎solutions/0122-best-time-to-buy-and-sell-stock-ii.md renamed to ‎solutions/1-1000/122-best-time-to-buy-and-sell-stock-ii.md
diff --git a/‎solutions/0123-best-time-to-buy-and-sell-stock-iii.md renamed to ‎solutions/1-1000/123-best-time-to-buy-and-sell-stock-iii.md b/‎solutions/0123-best-time-to-buy-and-sell-stock-iii.md renamed to ‎solutions/1-1000/123-best-time-to-buy-and-sell-stock-iii.md
diff --git a/‎solutions/0139-word-break.md renamed to ‎solutions/1-1000/139-word-break.md b/‎solutions/0139-word-break.md renamed to ‎solutions/1-1000/139-word-break.md
diff --git a/‎solutions/0188-best-time-to-buy-and-sell-stock-iv.md renamed to ‎solutions/1-1000/188-best-time-to-buy-and-sell-stock-iv.md b/‎solutions/0188-best-time-to-buy-and-sell-stock-iv.md renamed to ‎solutions/1-1000/188-best-time-to-buy-and-sell-stock-iv.md
diff --git a/‎solutions/0198-house-robber.md renamed to ‎solutions/1-1000/198-house-robber.md b/‎solutions/0198-house-robber.md renamed to ‎solutions/1-1000/198-house-robber.md
diff --git a/‎solutions/0200-number-of-islands-2.md renamed to ‎solutions/1-1000/200-number-of-islands-2.md
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diff --git a/‎solutions/0200-number-of-islands-3.md renamed to ‎solutions/1-1000/200-number-of-islands-3.md
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diff --git a/‎solutions/0213-house-robber-ii.md renamed to ‎solutions/1-1000/213-house-robber-ii.md b/‎solutions/0213-house-robber-ii.md renamed to ‎solutions/1-1000/213-house-robber-ii.md
diff --git a/‎solutions/0279-perfect-squares.md renamed to ‎solutions/1-1000/279-perfect-squares.md b/‎solutions/0279-perfect-squares.md renamed to ‎solutions/1-1000/279-perfect-squares.md
diff --git a/‎solutions/0300-longest-increasing-subsequence.md renamed to ‎solutions/1-1000/300-longest-increasing-subsequence.md b/‎solutions/0300-longest-increasing-subsequence.md renamed to ‎solutions/1-1000/300-longest-increasing-subsequence.md
diff --git a/‎solutions/0309-best-time-to-buy-and-sell-stock-with-cooldown.md renamed to ‎solutions/1-1000/309-best-time-to-buy-and-sell-stock-with-cooldown.md b/‎solutions/0309-best-time-to-buy-and-sell-stock-with-cooldown.md renamed to ‎solutions/1-1000/309-best-time-to-buy-and-sell-stock-with-cooldown.md
diff --git a/‎solutions/0322-coin-change.md renamed to ‎solutions/1-1000/322-coin-change.md b/‎solutions/0322-coin-change.md renamed to ‎solutions/1-1000/322-coin-change.md
diff --git a/‎solutions/0337-house-robber-iii.md renamed to ‎solutions/1-1000/337-house-robber-iii.md b/‎solutions/0337-house-robber-iii.md renamed to ‎solutions/1-1000/337-house-robber-iii.md
diff --git a/‎solutions/0377-combination-sum-iv.md renamed to ‎solutions/1-1000/377-combination-sum-iv.md b/‎solutions/0377-combination-sum-iv.md renamed to ‎solutions/1-1000/377-combination-sum-iv.md
diff --git a/‎solutions/0392-is-subsequence.md renamed to ‎solutions/1-1000/392-is-subsequence.md b/‎solutions/0392-is-subsequence.md renamed to ‎solutions/1-1000/392-is-subsequence.md
diff --git a/‎solutions/0416-partition-equal-subset-sum.md renamed to ‎solutions/1-1000/416-partition-equal-subset-sum.md b/‎solutions/0416-partition-equal-subset-sum.md renamed to ‎solutions/1-1000/416-partition-equal-subset-sum.md
diff --git a/‎solutions/0042-trapping-rain-water-2.md renamed to ‎solutions/1-1000/42-trapping-rain-water-2.md
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diff --git a/‎solutions/0042-trapping-rain-water.md renamed to ‎solutions/1-1000/42-trapping-rain-water.md
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diff --git a/‎solutions/0474-ones-and-zeroes.md renamed to ‎solutions/1-1000/474-ones-and-zeroes.md b/‎solutions/0474-ones-and-zeroes.md renamed to ‎solutions/1-1000/474-ones-and-zeroes.md
diff --git a/‎solutions/0494-target-sum.md renamed to ‎solutions/1-1000/494-target-sum.md
+1-1 b/‎solutions/0494-target-sum.md renamed to ‎solutions/1-1000/494-target-sum.md
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diff --git a/‎solutions/0496-next-greater-element-i.md renamed to ‎solutions/1-1000/496-next-greater-element-i.md b/‎solutions/0496-next-greater-element-i.md renamed to ‎solutions/1-1000/496-next-greater-element-i.md
@@ -13,59 +13,59 @@ I have planned a learning route for you. You just need to do the problems in the
 You can skip the more difficult problems and do them later.
 
 # Brute Force
-- [503. Next Greater Element II](solutions/0503-next-greater-element-ii.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
+- [503. Next Greater Element II](solutions/1-1000/503-next-greater-element-ii.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
 
 # Dynamic Programming
 ## Basics
-- [509. Fibonacci Number](solutions/0509-fibonacci-number.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
+- [509. Fibonacci Number](solutions/1-1000/509-fibonacci-number.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
 
 ## House Robber
-- [198. House Robber](solutions/0198-house-robber.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
-- [213. House Robber II](solutions/0213-house-robber-ii.md) was solved in _Python, JavaScript, Go_.
-- [337. House Robber III](solutions/0337-house-robber-iii.md) was solved in _Python, JavaScript, Go_ and **2** solutions.
+- [198. House Robber](solutions/1-1000/198-house-robber.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
+- [213. House Robber II](solutions/1-1000/213-house-robber-ii.md) was solved in _Python, JavaScript, Go_.
+- [337. House Robber III](solutions/1-1000/337-house-robber-iii.md) was solved in _Python, JavaScript, Go_ and **2** solutions.
 
 ## Knapsack Problems
 ### 0/1 Knapsack
-- [416. Partition Equal Subset Sum](solutions/0416-partition-equal-subset-sum.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_ and **2** solutions.
-- [1049. Last Stone Weight II](solutions/1049-last-stone-weight-ii.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_ and **2** solutions.
-- [494. Target Sum](solutions/0494-target-sum.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
-- [474. Ones and Zeroes](solutions/0474-ones-and-zeroes.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
+- [416. Partition Equal Subset Sum](solutions/1-1000/416-partition-equal-subset-sum.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_ and **2** solutions.
+- [1049. Last Stone Weight II](solutions/1001-2000/1049-last-stone-weight-ii.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_ and **2** solutions.
+- [494. Target Sum](solutions/1-1000/494-target-sum.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
+- [474. Ones and Zeroes](solutions/1-1000/474-ones-and-zeroes.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
 
 ### Unbounded Knapsack
-- [518. Coin Change II](solutions/0518-coin-change-ii.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
-- [377. Combination Sum IV](solutions/0377-combination-sum-iv.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
-- [322. Coin Change](solutions/0322-coin-change.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
-- [279. Perfect Squares](solutions/0279-perfect-squares.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
-- [139. Word Break](solutions/0139-word-break.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
+- [518. Coin Change II](solutions/1-1000/518-coin-change-ii.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
+- [377. Combination Sum IV](solutions/1-1000/377-combination-sum-iv.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
+- [322. Coin Change](solutions/1-1000/322-coin-change.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
+- [279. Perfect Squares](solutions/1-1000/279-perfect-squares.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
+- [139. Word Break](solutions/1-1000/139-word-break.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
 
 ## Stock Maximum Profit Problems
-- [121. Best Time to Buy and Sell Stock](solutions/0121-best-time-to-buy-and-sell-stock.md) was solved in _Python, JavaScript, Go_.
-- [122. Best Time to Buy and Sell Stock II](solutions/0122-best-time-to-buy-and-sell-stock-ii.md) was solved in _Python, JavaScript, Go_.
-- [714. Best Time to Buy and Sell Stock with Transaction Fee](solutions/0714-best-time-to-buy-and-sell-stock-with-transaction-fee.md) was solved in _Python, JavaScript, Go_.
-- [123. Best Time to Buy and Sell Stock III](solutions/0123-best-time-to-buy-and-sell-stock-iii.md) was solved in _Python, JavaScript, Go_.
-- [188. Best Time to Buy and Sell Stock IV](solutions/0188-best-time-to-buy-and-sell-stock-iv.md) was solved in _Python, JavaScript, Go_.
-- [309. Best Time to Buy and Sell Stock with Cooldown](solutions/0309-best-time-to-buy-and-sell-stock-with-cooldown.md) was solved in _Python, JavaScript, Go_.
+- [121. Best Time to Buy and Sell Stock](solutions/1-1000/121-best-time-to-buy-and-sell-stock.md) was solved in _Python, JavaScript, Go_.
+- [122. Best Time to Buy and Sell Stock II](solutions/1-1000/122-best-time-to-buy-and-sell-stock-ii.md) was solved in _Python, JavaScript, Go_.
+- [714. Best Time to Buy and Sell Stock with Transaction Fee](solutions/1-1000/714-best-time-to-buy-and-sell-stock-with-transaction-fee.md) was solved in _Python, JavaScript, Go_.
+- [123. Best Time to Buy and Sell Stock III](solutions/1-1000/123-best-time-to-buy-and-sell-stock-iii.md) was solved in _Python, JavaScript, Go_.
+- [188. Best Time to Buy and Sell Stock IV](solutions/1-1000/188-best-time-to-buy-and-sell-stock-iv.md) was solved in _Python, JavaScript, Go_.
+- [309. Best Time to Buy and Sell Stock with Cooldown](solutions/1-1000/309-best-time-to-buy-and-sell-stock-with-cooldown.md) was solved in _Python, JavaScript, Go_.
 
 ## Subsequence Problems
-- [674. Longest Continuous Increasing Subsequence](solutions/0674-longest-continuous-increasing-subsequence.md) was solved in _Python, Java, JavaScript, C#_.
-- [300. Longest Increasing Subsequence](solutions/0300-longest-increasing-subsequence.md) was solved in _Python, Java, JavaScript, C#_.
-- [718. Maximum Length of Repeated Subarray](solutions/0718-maximum-length-of-repeated-subarray.md) was solved in _Python, Java, JavaScript, C#_.
-- [1143. Longest Common Subsequence](solutions/1143-longest-common-subsequence.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
-- [1035. Uncrossed Lines](solutions/1035-uncrossed-lines.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
-- [53. Maximum Subarray](solutions/0053-maximum-subarray.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
-- [392. Is Subsequence](solutions/0392-is-subsequence.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
-- [583. Delete Operation for Two Strings](solutions/0583-delete-operation-for-two-strings.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
-- [72. Edit Distance](solutions/0072-edit-distance.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
+- [674. Longest Continuous Increasing Subsequence](solutions/1-1000/674-longest-continuous-increasing-subsequence.md) was solved in _Python, Java, JavaScript, C#_.
+- [300. Longest Increasing Subsequence](solutions/1-1000/300-longest-increasing-subsequence.md) was solved in _Python, Java, JavaScript, C#_.
+- [718. Maximum Length of Repeated Subarray](solutions/1-1000/718-maximum-length-of-repeated-subarray.md) was solved in _Python, Java, JavaScript, C#_.
+- [1143. Longest Common Subsequence](solutions/1001-2000/1143-longest-common-subsequence.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
+- [1035. Uncrossed Lines](solutions/1001-2000/1035-uncrossed-lines.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
+- [53. Maximum Subarray](solutions/1-1000/53-maximum-subarray.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
+- [392. Is Subsequence](solutions/1-1000/392-is-subsequence.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
+- [583. Delete Operation for Two Strings](solutions/1-1000/583-delete-operation-for-two-strings.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
+- [72. Edit Distance](solutions/1-1000/72-edit-distance.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
 
 # Monotonic Stack
-- [739. Daily Temperatures](solutions/0739-daily-temperatures.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
-- [496. Next Greater Element I](solutions/0496-next-greater-element-i.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
-- [42. Trapping Rain Water](solutions/0042-trapping-rain-water.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_ and **2** solutions.
-- [84. Largest Rectangle in Histogram](solutions/0084-largest-rectangle-in-histogram.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
+- [739. Daily Temperatures](solutions/1-1000/739-daily-temperatures.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
+- [496. Next Greater Element I](solutions/1-1000/496-next-greater-element-i.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
+- [42. Trapping Rain Water](solutions/1-1000/42-trapping-rain-water.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_ and **2** solutions.
+- [84. Largest Rectangle in Histogram](solutions/1-1000/84-largest-rectangle-in-histogram.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
 
 # Graph Theory
-- [797. All Paths From Source to Target](solutions/0797-all-paths-from-source-to-target.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_ and **2** solutions.
-- [200. Number of Islands](solutions/0200-number-of-islands.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_ and **3** solutions.
-- [695. Max Area of Island](solutions/0695-max-area-of-island.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
+- [797. All Paths From Source to Target](solutions/1-1000/797-all-paths-from-source-to-target.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_ and **2** solutions.
+- [200. Number of Islands](solutions/1-1000/200-number-of-islands.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_ and **3** solutions.
+- [695. Max Area of Island](solutions/1-1000/695-max-area-of-island.md) was solved in _Python, Java, C++, JavaScript, C#, Go, Ruby_.
 
 More LeetCode problems will be added soon...
@@ -37,11 +37,11 @@ Output: 3
 # Thoughts
 The island problem can be abstracted into a **graph theory** problem. This is an **undirected graph**:
 
-![](../images/graph_undirected_1.svg)
+![](../../images/graph_undirected_1.svg)
 
 And this graph may have multiple **connected components** (islands):
 
-![](../images/graph_undirected_2.png)
+![](../../images/graph_undirected_2.png)
 
 Finding the number of islands is to find the number of `connected components`.
 
@@ -57,29 +57,27 @@ Walk from one node to the adjacent node until all nodes on the island are visite
 1. Repeat the above two steps until all the lands have been `visited`.
 
 ### Solution 1: 'Depth-First Search' by Recursion
-Please click [Depth-First Search by Recursion Solution](0200-number-of-islands.md) for `200. Number of Islands` to view.
+Please click [Depth-First Search by Recursion Solution](200-number-of-islands.md) for `200. Number of Islands` to view.
 
 ## Solution 2: 'Depth-First Search' by Iteration
-![](../images/binary_tree_DFS_1.png)
+![](../../images/binary_tree_DFS_1.png)
 
 In solution 1, we have known how to traverse a graph by recursion. Computer language support for recursive calls is implemented through stacks.
 For every recursive solution, there is an iterative solution, which means the same problem can be solved using loops.
 The benefit of using iteration is better program performance. After all, recursive calls are expensive.
 
 Maintaining a stack by yourself can accomplish the same function as recursive calls.
 
-From this sample code bellow, you can see that starting from a node, through recursive calls, it goes up until it can't go any further, turns right, and continues up. The priority order of directions is `up, right, down, and left`.
-```python
-adjacent_points = [
-    (i, j - 1), # left
-    (i + 1, j), # down
-    (i, j + 1), # right
-    (i - 1, j), # up
-]
+From this sample code bellow, you can see that starting from a node, through recursive calls, it goes up until it can't go any further, turns right, and continues up. The priority order of directions is `up, right, down, left`.
+```java
+pointStack.push({i, j - 1}); // left
+pointStack.push({i + 1, j}); // down
+pointStack.push({i, j + 1}); // right
+pointStack.push({i - 1, j}); // up
 ```
 
 ## Solution 3: Breadth-First Search
-Please click [Breadth-First Search Solution](0200-number-of-islands-3.md) for `200. Number of Islands` to view.
+Please click [Breadth-First Search Solution](200-number-of-islands-3.md) for `200. Number of Islands` to view.
 
 ## Complexity
 * Time: `O(n * m)`.
 
@@ -37,11 +37,11 @@ Output: 3
 # Thoughts
 The island problem can be abstracted into a **graph theory** problem. This is an **undirected graph**:
 
-![](../images/graph_undirected_1.svg)
+![](../../images/graph_undirected_1.svg)
 
 And this graph may have multiple **connected components** (islands):
 
-![](../images/graph_undirected_2.png)
+![](../../images/graph_undirected_2.png)
 
 Finding the number of islands is to find the number of `connected components`.
 
@@ -57,13 +57,13 @@ Walk from one node to the adjacent node until all nodes on the island are visite
 1. Repeat the above two steps until all the lands have been `visited`.
 
 ### Solution 1: 'Depth-First Search' by Recursion
-Please click [Depth-First Search by Recursion Solution](0200-number-of-islands.md) for `200. Number of Islands` to view.
+Please click [Depth-First Search by Recursion Solution](200-number-of-islands.md) for `200. Number of Islands` to view.
 
 ## Solution 2: 'Depth-First Search' by Iteration
-Please click [Depth-First Search by Iteration Solution](0200-number-of-islands-2.md) for `200. Number of Islands` to view.
+Please click [Depth-First Search by Iteration Solution](200-number-of-islands-2.md) for `200. Number of Islands` to view.
 
 ## Solution 3: Breadth-First Search
-![](../images/binary_tree_BFS_1.gif)
+![](../../images/binary_tree_BFS_1.gif)
 
 As shown in the figure above, **breadth-first search** can be thought of as visiting nodes in rounds and rounds.
 It emphasizes first-in-first-out, so a **queue** is needed.
 
@@ -37,11 +37,11 @@ Output: 3
 # Thoughts
 The island problem can be abstracted into a **graph theory** problem. This is an **undirected graph**:
 
-![](../images/graph_undirected_1.svg)
+![](../../images/graph_undirected_1.svg)
 
 And this graph may have multiple **connected components** (islands):
 
-![](../images/graph_undirected_2.png)
+![](../../images/graph_undirected_2.png)
 
 Finding the number of islands is to find the number of `connected components`.
 
@@ -57,23 +57,21 @@ Walk from one node to the adjacent node until all nodes on the island are visite
 1. Repeat the above two steps until all the lands have been `visited`.
 
 ## Solution 1: 'Depth-First Search' by Recursion
-![](../images/binary_tree_DFS_1.png)
+![](../../images/binary_tree_DFS_1.png)
 
-From this sample code bellow, you can see that starting from a node, through recursive calls, it goes up until it can't go any further, turns right, and continues up. The priority order of directions is `up, right, down, and left`.
-```python
-adjacent_points = [
-   (i - 1, j), # up
-   (i, j + 1), # right
-   (i + 1, j), # down
-   (i, j - 1), # left
-]
+From this sample code bellow, you can see that starting from a node, through recursive calls, it goes up until it can't go any further, turns right, and continues up. The priority order of directions is `up, right, down, left`.
+```java
+depth_first_search(i - 1, j); // up
+depth_first_search(i, j + 1); // right
+depth_first_search(i + 1, j); // down
+depth_first_search(i, j - 1); // left
 ```
 
 ## Solution 2: 'Depth-First Search' by Iteration
-Please click [Depth-First Search by Iteration Solution](0200-number-of-islands-2.md) for `200. Number of Islands` to view.
+Please click [Depth-First Search by Iteration Solution](200-number-of-islands-2.md) for `200. Number of Islands` to view.
 
 ## Solution 3: Breadth-First Search
-Please click [Breadth-First Search Solution](0200-number-of-islands-3.md) for `200. Number of Islands` to view.
+Please click [Breadth-First Search Solution](200-number-of-islands-3.md) for `200. Number of Islands` to view.
 
 ## Complexity
 * Time: `O(n * m)`.
 
@@ -5,7 +5,7 @@ LeetCode problem link: [42. Trapping Rain Water](https://leetcode.com/problems/t
 Given `n` non-negative integers representing an elevation map where the width of each bar is `1`, compute how much water it can trap after raining.
 
 ### Example 1
-![](../images/examples/0042_1.png)
+![](../../images/examples/0042_1.png)
 ```
 Input: height = [0,1,0,2,1,0,1,3,2,1,2,1]
 Output: 6
@@ -33,10 +33,10 @@ This solution will follow **Monotonic Stack**'s common rule: **only calculating
 
 This common rule can be applied to calculating result for **most** of the **Monotonic Stack** problems.
 
-![](../images/0042.png)
+![](../../images/0042.png)
 
 ### Solution 1
-Please click [42. Trapping Rain Water (solution 1)](./0042-trapping-rain-water.md) to see it.
+Please click [42. Trapping Rain Water (solution 1)](42-trapping-rain-water.md) to see it.
 
 ### Complexity
 * Time: `O(n)`.
@@ -97,7 +97,7 @@ class Solution:
         return result
 ```
 
-![](../images/0042.png)
+![](../../images/0042.png)
 
 ## C++
 ```cpp
@@ -161,7 +161,7 @@ var trap = function (heights) {
 };
 ```
 
-![](../images/0042.png)
+![](../../images/0042.png)
 
 ## C#
 ```c#
@@ -228,7 +228,7 @@ func trap(heights []int) int {
 }
 ```
 
-![](../images/0042.png)
+![](../../images/0042.png)
 
 ## Ruby
 ```ruby
 
@@ -5,7 +5,7 @@ LeetCode problem link: [42. Trapping Rain Water](https://leetcode.com/problems/t
 Given `n` non-negative integers representing an elevation map where the width of each bar is `1`, compute how much water it can trap after raining.
 
 ### Example 1
-![](../images/examples/0042_1.png)
+![](../../images/examples/0042_1.png)
 ```
 Input: height = [0,1,0,2,1,0,1,3,2,1,2,1]
 Output: 6
@@ -36,14 +36,14 @@ This problem can be solved using **Monotonic Stack**.
     1) The right side (current item) is **no shorter** than the left side (the top of stack).
     2) The right side (current item) is **shorter** than the left side (the top of stack).
 
-![](../images/0042.png)
+![](../../images/0042.png)
 
 Detailed solutions will be given later, and now only the best practices in 7 languages are given.
 
 ### Solution 2
 The `solution 2` will follow **Monotonic Stack**'s common rule: **only calculating when `pop()` is happening**.
 
-Please click [42. Trapping Rain Water (solution 2)](./0042-trapping-rain-water-2.md) to see it.
+Please click [42. Trapping Rain Water (solution 2)](42-trapping-rain-water-2.md) to see it.
 
 ### Complexity
 * Time: `O(n)`.
@@ -108,7 +108,7 @@ class Solution:
         return result
 ```
 
-![](../images/0042.png)
+![](../../images/0042.png)
 
 ## C++
 ```cpp
@@ -174,7 +174,7 @@ var trap = function (heights) {
 };
 ```
 
-![](../images/0042.png)
+![](../../images/0042.png)
 
 ## C#
 ```c#
@@ -246,7 +246,7 @@ func trap(heights []int) int {
 }
 ```
 
-![](../images/0042.png)
+![](../../images/0042.png)
 
 ## Ruby
 ```ruby
 
@@ -38,7 +38,7 @@ Constraints:
 ```
 
 * This problem is quite difficult if you have not solved similar problems before. So before you start working on this question,
-it is recommended that you first work on another relatively simple question [416. Partition Equal Subset Sum](./0416-partition-equal-subset-sum.md) that is similar to this one.
+it is recommended that you first work on another relatively simple question [416. Partition Equal Subset Sum](416-partition-equal-subset-sum.md) that is similar to this one.
 
 ## Thoughts
 * When we see a set of numbers being used once to obtain another number through some calculation (just like this question), we can consider this to be a `0/1 Knapsack Problem`.