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/cpp/chapter_graph/graph_dfs.cpp

@@ -14,7 +14,7 @@ void dfs(GraphAdjList &graph, unordered_set<Vertex *> &visited, vector<Vertex *>
     // 遍历该顶点的所有邻接顶点
     for (Vertex *adjVet : graph.adjList[vet]) {
         if (visited.count(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);
     }