feat: Revised the book (#978)

* Sync recent changes to the revised Word.

* Revised the preface chapter

* Revised the introduction chapter

* Revised the computation complexity chapter

* Revised the chapter data structure

* Revised the chapter array and linked list

* Revised the chapter stack and queue

* Revised the chapter hashing

* Revised the chapter tree

* Revised the chapter heap

* Revised the chapter graph

* Revised the chapter searching

* Reivised the sorting chapter

* Revised the divide and conquer chapter

* Revised the chapter backtacking

* Revised the DP chapter

* Revised the greedy chapter

* Revised the appendix chapter

* Revised the preface chapter doubly

* Revised the figures

codes/java/chapter_graph/graph_adjacency_list.java

@@ -11,7 +11,7 @@ import utils.*;
 
 /* 基于邻接表实现的无向图类 */
 class GraphAdjList {
-    // 邻接表，key: 顶点，value：该顶点的所有邻接顶点
+    // 邻接表，key：顶点，value：该顶点的所有邻接顶点
     Map<Vertex, List<Vertex>> adjList;
 
     /* 构造方法 */

codes/java/chapter_graph/graph_adjacency_matrix.java

@@ -71,7 +71,7 @@ class GraphAdjMat {
         // 索引越界与相等处理
         if (i < 0 || j < 0 || i >= size() || j >= size() || i == j)
             throw new IndexOutOfBoundsException();
-        // 在无向图中，邻接矩阵沿主对角线对称，即满足 (i, j) == (j, i)
+        // 在无向图中，邻接矩阵关于主对角线对称，即满足 (i, j) == (j, i)
         adjMat.get(i).set(j, 1);
         adjMat.get(j).set(i, 1);
     }

codes/java/chapter_graph/graph_bfs.java

@@ -28,7 +28,7 @@ public class graph_bfs {
             // 遍历该顶点的所有邻接顶点
             for (Vertex adjVet : graph.adjList.get(vet)) {
                 if (visited.contains(adjVet))
-                    continue;        // 跳过已被访问过的顶点
+                    continue;        // 跳过已被访问的顶点
                 que.offer(adjVet);   // 只入队未访问的顶点
                 visited.add(adjVet); // 标记该顶点已被访问
             }

codes/java/chapter_graph/graph_dfs.java

@@ -17,7 +17,7 @@ public class graph_dfs {
         // 遍历该顶点的所有邻接顶点
         for (Vertex adjVet : graph.adjList.get(vet)) {
             if (visited.contains(adjVet))
-                continue; // 跳过已被访问过的顶点
+                continue; // 跳过已被访问的顶点
             // 递归访问邻接顶点
             dfs(graph, visited, res, adjVet);
         }