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‎README.md

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Original file line numberDiff line numberDiff line change
@@ -244,6 +244,7 @@ TypeScript-based LeetCode algorithm problem solutions, regularly updated.
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| <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- -->
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|-|-|-|-|-|-
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| 0121 |[Best Time to Buy and Sell Stock](src/main/ts/g0101_0200/s0121_best_time_to_buy_and_sell_stock/solution.ts)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(N)_Space_O(1) | 1 | 96.44
247+
| 0122 |[Best Time to Buy and Sell Stock II](src/main/ts/g0101_0200/s0122_best_time_to_buy_and_sell_stock_ii/solution.ts)| Medium | Top_Interview_Questions, Array, Dynamic_Programming, Greedy | 0 | 100.00
247248

248249
#### Day 8
249250

@@ -277,6 +278,7 @@ TypeScript-based LeetCode algorithm problem solutions, regularly updated.
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| <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- -->
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|-|-|-|-|-|-
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| 0120 |[Triangle](src/main/ts/g0101_0200/s0120_triangle/solution.ts)| Medium | Array, Dynamic_Programming | 0 | 100.00
280282

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#### Day 14
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@@ -884,6 +886,7 @@ TypeScript-based LeetCode algorithm problem solutions, regularly updated.
884886
| 0283 |[Move Zeroes](src/main/ts/g0201_0300/s0283_move_zeroes/solution.ts)| Easy | Top_100_Liked_Questions, Array, Two_Pointers, Big_O_Time_O(n)_Space_O(1) | 1 | 82.86
885887
| 0001 |[Two Sum](src/main/ts/g0001_0100/s0001_two_sum/solution.ts)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Big_O_Time_O(n)_Space_O(n), AI_can_be_used_to_solve_the_task | 1 | 89.70
886888
| 0058 |[Length of Last Word](src/main/ts/g0001_0100/s0058_length_of_last_word/solution.ts)| Easy | String | 0 | 100.00
889+
| 0122 |[Best Time to Buy and Sell Stock II](src/main/ts/g0101_0200/s0122_best_time_to_buy_and_sell_stock_ii/solution.ts)| Medium | Top_Interview_Questions, Array, Dynamic_Programming, Greedy | 0 | 100.00
887890
| 0080 |[Remove Duplicates from Sorted Array II](src/main/ts/g0001_0100/s0080_remove_duplicates_from_sorted_array_ii/solution.ts)| Medium | Array, Two_Pointers | 40 | 99.63
888891
| 0189 |[Rotate Array](src/main/ts/g0101_0200/s0189_rotate_array/solution.ts)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Math, Two_Pointers, Big_O_Time_O(n)_Space_O(1) | 1 | 86.17
889892
| 0055 |[Jump Game](src/main/ts/g0001_0100/s0055_jump_game/solution.ts)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Greedy, Big_O_Time_O(n)_Space_O(1) | 0 | 100.00
@@ -897,6 +900,7 @@ TypeScript-based LeetCode algorithm problem solutions, regularly updated.
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898901
| <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- -->
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|-|-|-|-|-|-
903+
| 0125 |[Valid Palindrome](src/main/ts/g0101_0200/s0125_valid_palindrome/solution.ts)| Easy | Top_Interview_Questions, String, Two_Pointers | 0 | 100.00
900904
| 0026 |[Remove Duplicates from Sorted Array](src/main/ts/g0001_0100/s0026_remove_duplicates_from_sorted_array/solution.ts)| Easy | Top_Interview_Questions, Array, Two_Pointers | 0 | 100.00
901905
| 0042 |[Trapping Rain Water](src/main/ts/g0001_0100/s0042_trapping_rain_water/solution.ts)| Hard | Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Two_Pointers, Stack, Monotonic_Stack, Big_O_Time_O(n)_Space_O(1) | 0 | 100.00
902906
| 0015 |[3Sum](src/main/ts/g0001_0100/s0015_3sum/solution.ts)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Two_Pointers, Big_O_Time_O(n\*log(n))_Space_O(n^2) | 30 | 91.56
@@ -971,6 +975,7 @@ TypeScript-based LeetCode algorithm problem solutions, regularly updated.
971975

972976
| <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- -->
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|-|-|-|-|-|-
978+
| 0120 |[Triangle](src/main/ts/g0101_0200/s0120_triangle/solution.ts)| Medium | Array, Dynamic_Programming | 0 | 100.00
974979
| 0139 |[Word Break](src/main/ts/g0101_0200/s0139_word_break/solution.ts)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Dynamic_Programming, Trie, Memoization, Big_O_Time_O(M+max\*N)_Space_O(M+N+max) | 4 | 76.41
975980
| 0152 |[Maximum Product Subarray](src/main/ts/g0101_0200/s0152_maximum_product_subarray/solution.ts)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(N)_Space_O(1) | 0 | 100.00
976981
| 0198 |[House Robber](src/main/ts/g0101_0200/s0198_house_robber/solution.ts)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(n)_Space_O(n) | 0 | 100.00
@@ -1016,6 +1021,7 @@ TypeScript-based LeetCode algorithm problem solutions, regularly updated.
10161021
| 0169 |[Majority Element](src/main/ts/g0101_0200/s0169_majority_element/solution.ts)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Sorting, Counting, Divide_and_Conquer, Big_O_Time_O(n)_Space_O(1) | 0 | 100.00
10171022
| 0189 |[Rotate Array](src/main/ts/g0101_0200/s0189_rotate_array/solution.ts)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Math, Two_Pointers, Big_O_Time_O(n)_Space_O(1) | 1 | 86.17
10181023
| 0121 |[Best Time to Buy and Sell Stock](src/main/ts/g0101_0200/s0121_best_time_to_buy_and_sell_stock/solution.ts)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(N)_Space_O(1) | 1 | 96.44
1024+
| 0122 |[Best Time to Buy and Sell Stock II](src/main/ts/g0101_0200/s0122_best_time_to_buy_and_sell_stock_ii/solution.ts)| Medium | Top_Interview_Questions, Array, Dynamic_Programming, Greedy | 0 | 100.00
10191025
| 0055 |[Jump Game](src/main/ts/g0001_0100/s0055_jump_game/solution.ts)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Greedy, Big_O_Time_O(n)_Space_O(1) | 0 | 100.00
10201026
| 0045 |[Jump Game II](src/main/ts/g0001_0100/s0045_jump_game_ii/solution.ts)| Medium | Top_100_Liked_Questions, Array, Dynamic_Programming, Greedy, Big_O_Time_O(n)_Space_O(1) | 1 | 84.27
10211027
| 0238 |[Product of Array Except Self](src/main/ts/g0201_0300/s0238_product_of_array_except_self/solution.ts)| Medium | Top_100_Liked_Questions, Array, Prefix_Sum, Big_O_Time_O(n^2)_Space_O(n) | 3 | 92.81
@@ -1032,6 +1038,7 @@ TypeScript-based LeetCode algorithm problem solutions, regularly updated.
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| <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- -->
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|-|-|-|-|-|-
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| 0125 |[Valid Palindrome](src/main/ts/g0101_0200/s0125_valid_palindrome/solution.ts)| Easy | Top_Interview_Questions, String, Two_Pointers | 0 | 100.00
10351042
| 0011 |[Container With Most Water](src/main/ts/g0001_0100/s0011_container_with_most_water/solution.ts)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Greedy, Two_Pointers, Big_O_Time_O(n)_Space_O(1) | 2 | 80.13
10361043
| 0015 |[3Sum](src/main/ts/g0001_0100/s0015_3sum/solution.ts)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Two_Pointers, Big_O_Time_O(n\*log(n))_Space_O(n^2) | 30 | 91.56
10371044

@@ -1100,6 +1107,7 @@ TypeScript-based LeetCode algorithm problem solutions, regularly updated.
11001107
| 0101 |[Symmetric Tree](src/main/ts/g0101_0200/s0101_symmetric_tree/solution.ts)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(N)_Space_O(log(N)) | 0 | 100.00
11011108
| 0105 |[Construct Binary Tree from Preorder and Inorder Traversal](src/main/ts/g0101_0200/s0105_construct_binary_tree_from_preorder_and_inorder_traversal/solution.ts)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Tree, Binary_Tree, Divide_and_Conquer, Big_O_Time_O(N)_Space_O(N) | 2 | 93.38
11021109
| 0106 |[Construct Binary Tree from Inorder and Postorder Traversal](src/main/ts/g0101_0200/s0106_construct_binary_tree_from_inorder_and_postorder_traversal/solution.ts)| Medium | Array, Hash_Table, Tree, Binary_Tree, Divide_and_Conquer | 1 | 98.78
1110+
| 0117 |[Populating Next Right Pointers in Each Node II](src/main/ts/g0101_0200/s0117_populating_next_right_pointers_in_each_node_ii/solution.ts)| Medium | Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Linked_List | 47 | 97.74
11031111
| 0114 |[Flatten Binary Tree to Linked List](src/main/ts/g0101_0200/s0114_flatten_binary_tree_to_linked_list/solution.ts)| Medium | Top_100_Liked_Questions, Depth_First_Search, Tree, Binary_Tree, Stack, Linked_List, Big_O_Time_O(N)_Space_O(N) | 0 | 100.00
11041112
| 0112 |[Path Sum](src/main/ts/g0101_0200/s0112_path_sum/solution.ts)| Easy | Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree | 0 | 100.00
11051113
| 0124 |[Binary Tree Maximum Path Sum](src/main/ts/g0101_0200/s0124_binary_tree_maximum_path_sum/solution.ts)| Hard | Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Depth_First_Search, Tree, Binary_Tree, Big_O_Time_O(N)_Space_O(N) | 2 | 71.11
@@ -1211,11 +1219,13 @@ TypeScript-based LeetCode algorithm problem solutions, regularly updated.
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| <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- --> | <!-- -->
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|-|-|-|-|-|-
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| 0120 |[Triangle](src/main/ts/g0101_0200/s0120_triangle/solution.ts)| Medium | Array, Dynamic_Programming | 0 | 100.00
12141223
| 0064 |[Minimum Path Sum](src/main/ts/g0001_0100/s0064_minimum_path_sum/solution.ts)| Medium | Top_100_Liked_Questions, Array, Dynamic_Programming, Matrix, Big_O_Time_O(m\*n)_Space_O(m\*n) | 4 | 70.73
12151224
| 0063 |[Unique Paths II](src/main/ts/g0001_0100/s0063_unique_paths_ii/solution.ts)| Medium | Array, Dynamic_Programming, Matrix | 0 | 100.00
12161225
| 0005 |[Longest Palindromic Substring](src/main/ts/g0001_0100/s0005_longest_palindromic_substring/solution.ts)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, String, Dynamic_Programming, Big_O_Time_O(n)_Space_O(n) | 8 | 99.14
12171226
| 0097 |[Interleaving String](src/main/ts/g0001_0100/s0097_interleaving_string/solution.ts)| Medium | String, Dynamic_Programming | 43 | 97.65
12181227
| 0072 |[Edit Distance](src/main/ts/g0001_0100/s0072_edit_distance/solution.ts)| Medium | Top_100_Liked_Questions, String, Dynamic_Programming, Big_O_Time_O(n^2)_Space_O(n2) | 6 | 93.83
1228+
| 0123 |[Best Time to Buy and Sell Stock III](src/main/ts/g0101_0200/s0123_best_time_to_buy_and_sell_stock_iii/solution.ts)| Hard | Array, Dynamic_Programming | 5 | 85.07
12191229
| 0221 |[Maximal Square](src/main/ts/g0201_0300/s0221_maximal_square/solution.ts)| Medium | Array, Dynamic_Programming, Matrix, Big_O_Time_O(m\*n)_Space_O(m\*n) | 18 | 59.02
12201230

12211231
### Data Structure I
@@ -1512,6 +1522,7 @@ TypeScript-based LeetCode algorithm problem solutions, regularly updated.
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|-|-|-|-|-|-
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| 0070 |[Climbing Stairs](src/main/ts/g0001_0100/s0070_climbing_stairs/solution.ts)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Math, Memoization, Big_O_Time_O(n)_Space_O(n) | 0 | 100.00
15141524
| 0198 |[House Robber](src/main/ts/g0101_0200/s0198_house_robber/solution.ts)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(n)_Space_O(n) | 0 | 100.00
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| 0120 |[Triangle](src/main/ts/g0101_0200/s0120_triangle/solution.ts)| Medium | Array, Dynamic_Programming | 0 | 100.00
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15161527
#### Day 13 Bit Manipulation
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| 0117 |[Populating Next Right Pointers in Each Node II](src/main/ts/g0101_0200/s0117_populating_next_right_pointers_in_each_node_ii/solution.ts)| Medium | Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Linked_List | 47 | 97.74
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#### Day 8 Breadth First Search Depth First Search
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@@ -1705,8 +1717,13 @@ TypeScript-based LeetCode algorithm problem solutions, regularly updated.
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| 0136 |[Single Number](src/main/ts/g0101_0200/s0136_single_number/solution.ts)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Array, Bit_Manipulation, Data_Structure_II_Day_1_Array, Algorithm_I_Day_14_Bit_Manipulation, Udemy_Integers, Top_Interview_150_Bit_Manipulation, Big_O_Time_O(N)_Space_O(1) | 1 | 78.27
17061718
| 0131 |[Palindrome Partitioning](src/main/ts/g0101_0200/s0131_palindrome_partitioning/solution.ts)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, String, Dynamic_Programming, Backtracking, Big_O_Time_O(N\*2^N)_Space_O(2^N\*N) | 13 | 94.96
17071719
| 0128 |[Longest Consecutive Sequence](src/main/ts/g0101_0200/s0128_longest_consecutive_sequence/solution.ts)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Union_Find, Top_Interview_150_Hashmap, Big_O_Time_O(N_log_N)_Space_O(1) | 34 | 90.07
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| 0125 |[Valid Palindrome](src/main/ts/g0101_0200/s0125_valid_palindrome/solution.ts)| Easy | Top_Interview_Questions, String, Two_Pointers, Udemy_Two_Pointers, Top_Interview_150_Two_Pointers | 0 | 100.00
17081721
| 0124 |[Binary Tree Maximum Path Sum](src/main/ts/g0101_0200/s0124_binary_tree_maximum_path_sum/solution.ts)| Hard | Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Depth_First_Search, Tree, Binary_Tree, Udemy_Tree_Stack_Queue, Top_Interview_150_Binary_Tree_General, Big_O_Time_O(N)_Space_O(N) | 2 | 71.11
1722+
| 0123 |[Best Time to Buy and Sell Stock III](src/main/ts/g0101_0200/s0123_best_time_to_buy_and_sell_stock_iii/solution.ts)| Hard | Array, Dynamic_Programming, Top_Interview_150_Multidimensional_DP | 5 | 85.07
1723+
| 0122 |[Best Time to Buy and Sell Stock II](src/main/ts/g0101_0200/s0122_best_time_to_buy_and_sell_stock_ii/solution.ts)| Medium | Top_Interview_Questions, Array, Dynamic_Programming, Greedy, Dynamic_Programming_I_Day_7, Udemy_Arrays, Top_Interview_150_Array/String | 0 | 100.00
17091724
| 0121 |[Best Time to Buy and Sell Stock](src/main/ts/g0101_0200/s0121_best_time_to_buy_and_sell_stock/solution.ts)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Data_Structure_I_Day_3_Array, Dynamic_Programming_I_Day_7, Level_1_Day_5_Greedy, Udemy_Arrays, Top_Interview_150_Array/String, Big_O_Time_O(N)_Space_O(1) | 1 | 96.44
1725+
| 0120 |[Triangle](src/main/ts/g0101_0200/s0120_triangle/solution.ts)| Medium | Array, Dynamic_Programming, Algorithm_I_Day_12_Dynamic_Programming, Dynamic_Programming_I_Day_13, Udemy_Dynamic_Programming, Top_Interview_150_Multidimensional_DP | 0 | 100.00
1726+
| 0117 |[Populating Next Right Pointers in Each Node II](src/main/ts/g0101_0200/s0117_populating_next_right_pointers_in_each_node_ii/solution.ts)| Medium | Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Linked_List, Algorithm_II_Day_7_Breadth_First_Search_Depth_First_Search, Top_Interview_150_Binary_Tree_General | 47 | 97.74
17101727
| 0114 |[Flatten Binary Tree to Linked List](src/main/ts/g0101_0200/s0114_flatten_binary_tree_to_linked_list/solution.ts)| Medium | Top_100_Liked_Questions, Depth_First_Search, Tree, Binary_Tree, Stack, Linked_List, Udemy_Linked_List, Top_Interview_150_Binary_Tree_General, Big_O_Time_O(N)_Space_O(N) | 0 | 100.00
17111728
| 0112 |[Path Sum](src/main/ts/g0101_0200/s0112_path_sum/solution.ts)| Easy | Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Data_Structure_I_Day_12_Tree, Top_Interview_150_Binary_Tree_General | 0 | 100.00
17121729
| 0108 |[Convert Sorted Array to Binary Search Tree](src/main/ts/g0101_0200/s0108_convert_sorted_array_to_binary_search_tree/solution.ts)| Easy | Top_Interview_Questions, Array, Tree, Binary_Tree, Binary_Search_Tree, Divide_and_Conquer, Data_Structure_II_Day_15_Tree, Level_2_Day_9_Binary_Search_Tree, Udemy_Tree_Stack_Queue, Top_Interview_150_Divide_and_Conquer | 0 | 100.00

‎src/main/ts/com_github_leetcode/_node.ts

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class _Node {
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val: number
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left: _Node | null
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right: _Node | null
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next: _Node | null
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constructor(val?: number, left?: _Node, right?: _Node, next?: _Node) {
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this.val = val === undefined ? 0 : val
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this.left = left === undefined ? null : left
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this.right = right === undefined ? null : right
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this.next = next === undefined ? null : next
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}
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}
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export { _Node }

‎src/main/ts/g0101_0200/s0117_populating_next_right_pointers_in_each_node_ii/readme.md

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117\. Populating Next Right Pointers in Each Node II
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Medium
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Given a binary tree
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struct Node { int val; Node \*left; Node \*right; Node \*next; }
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Populate each next pointer to point to its next right node. If there is no next right node, the next pointer should be set to `NULL`.
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Initially, all next pointers are set to `NULL`.
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**Example 1:**
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![](https://assets.leetcode.com/uploads/2019/02/15/117_sample.png)
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**Input:** root = [1,2,3,4,5,null,7]
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**Output:** [1,#,2,3,#,4,5,7,#]
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**Explanation:** Given the above binary tree (Figure A), your function should populate each next pointer to point to its next right node, just like in Figure B. The serialized output is in level order as connected by the next pointers, with '#' signifying the end of each level.
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**Example 2:**
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**Input:** root = []
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**Output:** []
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**Constraints:**
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* The number of nodes in the tree is in the range `[0, 6000]`.
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* `-100 <= Node.val <= 100`
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**Follow-up:**
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* You may only use constant extra space.
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* The recursive approach is fine. You may assume implicit stack space does not count as extra space for this problem.

‎src/main/ts/g0101_0200/s0117_populating_next_right_pointers_in_each_node_ii/solution.ts

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// #Medium #Depth_First_Search #Breadth_First_Search #Tree #Binary_Tree #Linked_List
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// #Algorithm_II_Day_7_Breadth_First_Search_Depth_First_Search
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// #Top_Interview_150_Binary_Tree_General #2025_04_07_Time_47_ms_(97.74%)_Space_61.19_MB_(53.38%)
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import { _Node } from "../../com_github_leetcode/_node"
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/**
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* Definition for _Node.
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* class _Node {
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* val: number
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* left: _Node | null
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* right: _Node | null
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* next: _Node | null
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*
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* constructor(val?: number, left?: _Node, right?: _Node, next?: _Node) {
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* this.val = (val===undefined ? 0 : val)
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* this.left = (left===undefined ? null : left)
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* this.right = (right===undefined ? null : right)
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* this.next = (next===undefined ? null : next)
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* }
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* }
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*/
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function connect(root: _Node | null): _Node | null {
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if (!root) {
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return null
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}
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root.next = null
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let dummyHead = new _Node()
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let current: _Node | null = root
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while (current) {
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// reset dummyHead
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dummyHead.next = null
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let child = dummyHead
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// traverse the current level
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while (current) {
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if (current.left) {
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child.next = current.left
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child = child.next
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}
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if (current.right) {
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child.next = current.right
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child = child.next
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}
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current = current.next
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}
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// move on to the next level
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current = dummyHead.next
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}
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return root
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}
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export { connect }

‎src/main/ts/g0101_0200/s0120_triangle/readme.md

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120\. Triangle
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Medium
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Given a `triangle` array, return _the minimum path sum from top to bottom_.
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For each step, you may move to an adjacent number of the row below. More formally, if you are on index `i` on the current row, you may move to either index `i` or index `i + 1` on the next row.
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**Example 1:**
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**Input:** triangle = [[2],[3,4],[6,5,7],[4,1,8,3]]
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**Output:** 11
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**Explanation:**
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The triangle looks like:
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2
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3 4
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6 5 7
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4 1 8 3
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The minimum path sum from top to bottom is 2 + 3 + 5 + 1 = 11 (underlined above).
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**Example 2:**
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**Input:** triangle = [[-10]]
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**Output:** -10
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**Constraints:**
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* `1 <= triangle.length <= 200`
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* `triangle[0].length == 1`
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* `triangle[i].length == triangle[i - 1].length + 1`
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* <code>-10<sup>4</sup> <= triangle[i][j] <= 10<sup>4</sup></code>
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**Follow up:** Could you do this using only `O(n)` extra space, where `n` is the total number of rows in the triangle?

‎src/main/ts/g0101_0200/s0120_triangle/solution.ts

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Original file line numberDiff line numberDiff line change
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// #Medium #Array #Dynamic_Programming #Algorithm_I_Day_12_Dynamic_Programming
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// #Dynamic_Programming_I_Day_13 #Udemy_Dynamic_Programming #Top_Interview_150_Multidimensional_DP
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// #2025_04_07_Time_0_ms_(100.00%)_Space_58.24_MB_(28.24%)
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function minimumTotal(triangle: number[][]): number {
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if (!triangle || triangle.length === 0) {
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return 0
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}
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const rows = triangle.length
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const cols = triangle[rows - 1].length
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const dp: number[][] = Array.from({ length: rows }, () => Array(cols).fill(-10001))
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function dfs(row: number, col: number): number {
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if (row >= triangle.length) {
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return 0
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}
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if (dp[row][col] !== -10001) {
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return dp[row][col]
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}
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const sum = triangle[row][col] + Math.min(
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dfs(row + 1, col),
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dfs(row + 1, col + 1)
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)
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dp[row][col] = sum
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return sum
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}
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return dfs(0, 0)
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}
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export { minimumTotal }

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