二刷37

Author: diguage

README.adoc

@@ -285,12 +285,12 @@ TIP: **公众号的微信号是: `jikerizhi`**。__因为众所周知的原因
 |Medium
 |
 
-//|{counter:codes}
-//|{leetcode_base_url}/sudoku-solver/[37. Sudoku Solver^]
-//|{source_base_url}/_0037_SudokuSolver.java[Java]
-//|{doc_base_url}/0037-sudoku-solver.adoc[题解]
-//|Hard
-//|
+|{counter:codes}
+|{leetcode_base_url}/sudoku-solver/[37. Sudoku Solver^]
+|{source_base_url}/_0037_SudokuSolver.java[Java]
+|{doc_base_url}/0037-sudoku-solver.adoc[题解]
+|Hard
+|
 
 |{counter:codes}
 |{leetcode_base_url}/count-and-say/[38. Count and Say^]

docs/0000-23-backtrack.adoc

@@ -7,6 +7,34 @@
 
 回溯优化，重要的是，要学会剪枝！
 
+回溯三部曲：
+
+. 定义递归函数以及参数
+. 确定递归终止条件
+. 思考递归单层搜索逻辑
+
+== 经典题目
+
+image::images/backtrack-01.png[{image_attr}]
+
+. xref:0077-combinations.adoc[77. Combinations]
+. xref:0216-combination-sum-iii.adoc[216. Combination Sum III]
+. xref:0017-letter-combinations-of-a-phone-number.adoc[17. Letter Combinations of a Phone Number]
+. xref:0039-combination-sum.adoc[39. Combination Sum]
+. xref:0040-combination-sum-ii.adoc[40. Combination Sum II]
+. xref:0131-palindrome-partitioning.adoc[131. Palindrome Partitioning]
+. xref:0093-restore-ip-addresses.adoc[93. Restore IP Addresses]
+. xref:0078-subsets.adoc[78. Subsets]
+. xref:0090-subsets-ii.adoc[90. Subsets II]
+. xref:0491-increasing-subsequences.adoc[491. Increasing Subsequences]
+. xref:0046-permutations.adoc[46. Permutations]
+. xref:0047-permutations-ii.adoc[47. Permutations II]
+. xref:0332-reconstruct-itinerary.adoc[332. Reconstruct Itinerary]
+. xref:0051-n-queens.adoc[51. N-Queens]
+. xref:0052-n-queens-ii.adoc[52. N-Queens II]
+. xref:0037-sudoku-solver.adoc[37. Sudoku Solver]
+
+
 == 附加题
 
 . 写程序尝试生成递归调用树。

docs/0037-sudoku-solver.adoc

@@ -15,11 +15,11 @@ A sudoku solution must satisfy *all of the following rules*:
 
 Empty cells are indicated by the character `'.'`.
 
-image::images/0037-1.png[{image_attr}]
+image::images/0037-01.png[{image_attr}]
 
 [.small]#A sudoku puzzle...#
 
-image::images/0037-2.png[{image_attr}]
+image::images/0037-02.png[{image_attr}]
 
 [.small]#...and its solution numbers marked in red.#
 
@@ -33,13 +33,34 @@ image::images/0037-2.png[{image_attr}]
 
 这道题特别需要关注的点是：只要找到一个解就可以了，不需要求全部解。所以，需要重点思考的是，如何在找到第一个解时，就立即停止搜索。
 
+递归树
+
+image::images/0037-03.png[{image_attr}]
+
 [[src-0037]]
+[tabs]
+====
+一刷::
++
+--
 [{java_src_attr}]
 ----
 include::{sourcedir}/_0037_SudokuSolver.java[tag=answer]
 ----
+--
+
+二刷::
++
+--
+[{java_src_attr}]
+----
+include::{sourcedir}/_0037_SudokuSolver_2.java[tag=answer]
+----
+--
+====
 
 == 参考资料
 
 . https://mp.weixin.qq.com/s/VCirGskFGPln-S2LGFTgKg[搞懂回溯算法，我终于能做数独了^]
+. https://leetcode.cn/problems/sudoku-solver/solutions/414261/37-jie-shu-du-hui-su-sou-suo-suan-fa-xiang-jie-by-/[37. 解数独 - 「代码随想录」带你学透回溯算法！^]
 

docs/images/0037-1.png renamed to docs/images/0037-01.png

@@ -444,6 +444,11 @@
 |{doc_base_url}/0416-partition-equal-subset-sum.adoc[题解]
 |动态规划，0/1背包问题
 
+|{counter:codes}
+|{leetcode_base_url}/sudoku-solver/[37. Sudoku Solver^]
+|{doc_base_url}/0037-sudoku-solver.adoc[题解]
+|回溯
+
 
 |===
 

docs/images/0037-1.webp renamed to docs/images/0037-01.webp

@@ -12,6 +12,10 @@
  */
 public class _0037_SudokuSolver {
   // tag::answer[]
+    /**
+     *  * @author D瓜哥 · https://www.diguage.com
+     *  * @since 2020-03-25 09:34
+     */
     public void solveSudoku(char[][] board) {
         backtrack(board, 0);
     }