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Retranslate the complete English edition from Simplified Chinese (#2010)

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* Retranslate the complete English edition from Simplified Chinese

* Polish three English explanations after reader-focused review
This commit is contained in:
Yudong Jin
2026-10-31 03:35:51 +08:00
committed by GitHub
parent ef46e2ed95
commit 14c314c08c
1502 changed files with 29459 additions and 23517 deletions
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44
en/codes/java/chapter_graph/graph_adjacency_list.java
View File

@@ -9,9 +9,9 @@ package chapter_graph;
import java.util.*;
import utils.*;
/* Undirected graph class based on adjacency list */
/* Undirected graph class implemented with an adjacency list */
class GraphAdjList {
// Adjacency list, key: vertex, value: all adjacent vertices of that vertex
// Adjacency list: key is a vertex, value is the list of all its neighbors
Map<Vertex, List<Vertex>> adjList;
/* Constructor */
@@ -30,7 +30,7 @@ class GraphAdjList {
return adjList.size();
}
/* Add edge */
/* Add an edge */
public void addEdge(Vertex vet1, Vertex vet2) {
if (!adjList.containsKey(vet1) || !adjList.containsKey(vet2) || vet1 == vet2)
throw new IllegalArgumentException();
@@ -39,7 +39,7 @@ class GraphAdjList {
adjList.get(vet2).add(vet1);
}
/* Remove edge */
/* Remove an edge */
public void removeEdge(Vertex vet1, Vertex vet2) {
if (!adjList.containsKey(vet1) || !adjList.containsKey(vet2) || vet1 == vet2)
throw new IllegalArgumentException();
@@ -48,27 +48,27 @@ class GraphAdjList {
adjList.get(vet2).remove(vet1);
}
/* Add vertex */
/* Add a vertex */
public void addVertex(Vertex vet) {
if (adjList.containsKey(vet))
return;
// Add a new linked list in the adjacency list
// Add a new list to the adjacency list
adjList.put(vet, new ArrayList<>());
}
/* Remove vertex */
/* Remove a vertex */
public void removeVertex(Vertex vet) {
if (!adjList.containsKey(vet))
throw new IllegalArgumentException();
// Remove the linked list corresponding to vertex vet in the adjacency list
// Remove the list corresponding to vertex vet from the adjacency list
adjList.remove(vet);
// Traverse the linked lists of other vertices and remove all edges containing vet
// Traverse the lists of the other vertices and remove all edges incident to vet
for (List<Vertex> list : adjList.values()) {
list.remove(vet);
}
}
/* Print adjacency list */
/* Print the adjacency list */
public void print() {
System.out.println("Adjacency list =");
for (Map.Entry<Vertex, List<Vertex>> pair : adjList.entrySet()) {
@@ -82,36 +82,36 @@ class GraphAdjList {
public class graph_adjacency_list {
public static void main(String[] args) {
/* Add edge */
/* Initialize the undirected graph */
Vertex[] v = Vertex.valsToVets(new int[] { 1, 3, 2, 5, 4 });
Vertex[][] edges = { { v[0], v[1] }, { v[0], v[3] }, { v[1], v[2] },
{ v[2], v[3] }, { v[2], v[4] }, { v[3], v[4] } };
GraphAdjList graph = new GraphAdjList(edges);
System.out.println("\nAfter initialization, graph is");
System.out.println("\nGraph after initialization:");
graph.print();
/* Add edge */
// Vertices 1, 3 are v[0], v[1]
/* Add an edge */
// Vertices 1 and 2 are v[0] and v[2]
graph.addEdge(v[0], v[2]);
System.out.println("\nAfter adding edge 1-2, graph is");
System.out.println("\nGraph after adding edge 1-2:");
graph.print();
/* Remove edge */
// Vertex 3 is v[1]
/* Remove an edge */
// Vertices 1 and 3 are v[0] and v[1]
graph.removeEdge(v[0], v[1]);
System.out.println("\nAfter removing edge 1-3, graph is");
System.out.println("\nGraph after removing edge 1-3:");
graph.print();
/* Add vertex */
/* Add a vertex */
Vertex v5 = new Vertex(6);
graph.addVertex(v5);
System.out.println("\nAfter adding vertex 6, graph is");
System.out.println("\nGraph after adding vertex 6:");
graph.print();
/* Remove vertex */
/* Remove a vertex */
// Vertex 3 is v[1]
graph.removeVertex(v[1]);
System.out.println("\nAfter removing vertex 3, graph is");
System.out.println("\nGraph after removing vertex 3:");
graph.print();
}
}

66
en/codes/java/chapter_graph/graph_adjacency_matrix.java
View File

@@ -9,21 +9,21 @@ package chapter_graph;
import utils.*;
import java.util.*;
/* Undirected graph class based on adjacency matrix */
/* Undirected graph class implemented with an adjacency matrix */
class GraphAdjMat {
List<Integer> vertices; // Vertex list, where the element represents the "vertex value" and the index represents the "vertex index"
List<List<Integer>> adjMat; // Adjacency matrix, where the row and column indices correspond to the "vertex index"
List<Integer> vertices; // Vertex list: elements are vertex values, and indices are vertex indices
List<List<Integer>> adjMat; // Adjacency matrix: row and column indices correspond to vertex indices
/* Constructor */
public GraphAdjMat(int[] vertices, int[][] edges) {
this.vertices = new ArrayList<>();
this.adjMat = new ArrayList<>();
// Add vertex
// Add a vertex
for (int val : vertices) {
addVertex(val);
}
// Add edge
// Note that the edges elements represent vertex indices, i.e., corresponding to the vertices element indices
// Add an edge
// Note that the entries in edges are vertex indices, corresponding to element indices in vertices
for (int[] e : edges) {
addEdge(e[0], e[1]);
}
@@ -34,10 +34,10 @@ class GraphAdjMat {
return vertices.size();
}
/* Add vertex */
/* Add a vertex */
public void addVertex(int val) {
int n = size();
// Add the value of the new vertex to the vertex list
// Append the new vertex value to the vertex list
vertices.add(val);
// Add a row to the adjacency matrix
List<Integer> newRow = new ArrayList<>(n);
@@ -51,42 +51,42 @@ class GraphAdjMat {
}
}
/* Remove vertex */
/* Remove a vertex */
public void removeVertex(int index) {
if (index >= size())
throw new IndexOutOfBoundsException();
// Remove the vertex at index from the vertex list
// Remove the vertex at index `index` from the vertex list
vertices.remove(index);
// Remove the row at index from the adjacency matrix
// Remove row `index` from the adjacency matrix
adjMat.remove(index);
// Remove the column at index from the adjacency matrix
// Remove column `index` from the adjacency matrix
for (List<Integer> row : adjMat) {
row.remove(index);
}
}
/* Add edge */
// Parameters i, j correspond to the vertices element indices
/* Add an edge */
// Parameters i and j are element indices in vertices
public void addEdge(int i, int j) {
// Handle index out of bounds and equality
// Handle out-of-bounds or equal indices
if (i < 0 || j < 0 || i >= size() || j >= size() || i == j)
throw new IndexOutOfBoundsException();
// In an undirected graph, the adjacency matrix is symmetric about the main diagonal, i.e., (i, j) == (j, i)
// For an undirected graph, the adjacency matrix is symmetric about its main diagonal: entries (i, j) and (j, i) are equal
adjMat.get(i).set(j, 1);
adjMat.get(j).set(i, 1);
}
/* Remove edge */
// Parameters i, j correspond to the vertices element indices
/* Remove an edge */
// Parameters i and j are element indices in vertices
public void removeEdge(int i, int j) {
// Handle index out of bounds and equality
// Handle out-of-bounds or equal indices
if (i < 0 || j < 0 || i >= size() || j >= size() || i == j)
throw new IndexOutOfBoundsException();
adjMat.get(i).set(j, 0);
adjMat.get(j).set(i, 0);
}
/* Print adjacency matrix */
/* Print the adjacency matrix */
public void print() {
System.out.print("Vertex list = ");
System.out.println(vertices);
@@ -97,35 +97,35 @@ class GraphAdjMat {
public class graph_adjacency_matrix {
public static void main(String[] args) {
/* Add edge */
// Note that the edges elements represent vertex indices, i.e., corresponding to the vertices element indices
/* Initialize the undirected graph */
// Note that the entries in edges are vertex indices, corresponding to element indices in vertices
int[] vertices = { 1, 3, 2, 5, 4 };
int[][] edges = { { 0, 1 }, { 0, 3 }, { 1, 2 }, { 2, 3 }, { 2, 4 }, { 3, 4 } };
GraphAdjMat graph = new GraphAdjMat(vertices, edges);
System.out.println("\nAfter initialization, graph is");
System.out.println("\nGraph after initialization:");
graph.print();
/* Add edge */
// Add vertex
/* Add an edge */
// Vertices 1 and 2 have indices 0 and 2, respectively
graph.addEdge(0, 2);
System.out.println("\nAfter adding edge 1-2, graph is");
System.out.println("\nGraph after adding edge 1-2:");
graph.print();
/* Remove edge */
// Vertices 1, 3 have indices 0, 1 respectively
/* Remove an edge */
// Vertices 1 and 3 have indices 0 and 1, respectively
graph.removeEdge(0, 1);
System.out.println("\nAfter removing edge 1-3, graph is");
System.out.println("\nGraph after removing edge 1-3:");
graph.print();
/* Add vertex */
/* Add a vertex */
graph.addVertex(6);
System.out.println("\nAfter adding vertex 6, graph is");
System.out.println("\nGraph after adding vertex 6:");
graph.print();
/* Remove vertex */
/* Remove a vertex */
// Vertex 3 has index 1
graph.removeVertex(1);
System.out.println("\nAfter removing vertex 3, graph is");
System.out.println("\nGraph after removing vertex 3:");
graph.print();
}
}

24
en/codes/java/chapter_graph/graph_bfs.java
View File

@@ -11,45 +11,45 @@ import utils.*;
public class graph_bfs {
/* Breadth-first traversal */
// Use adjacency list to represent the graph, in order to obtain all adjacent vertices of a specified vertex
// Represent the graph with an adjacency list to access all neighbors of a given vertex
static List<Vertex> graphBFS(GraphAdjList graph, Vertex startVet) {
// Vertex traversal sequence
List<Vertex> res = new ArrayList<>();
// Hash set for recording vertices that have been visited
// Hash set recording visited vertices
Set<Vertex> visited = new HashSet<>();
visited.add(startVet);
// Queue used to implement BFS
// Use a queue to implement BFS
Queue<Vertex> que = new LinkedList<>();
que.offer(startVet);
// Starting from vertex vet, loop until all vertices are visited
// Starting from startVet, loop until all reachable vertices have been visited
while (!que.isEmpty()) {
Vertex vet = que.poll(); // Dequeue the front vertex
res.add(vet); // Record visited vertex
// Traverse all adjacent vertices of this vertex
res.add(vet); // Record the visited vertex
// Traverse all neighbors of this vertex
for (Vertex adjVet : graph.adjList.get(vet)) {
if (visited.contains(adjVet))
continue; // Skip vertices that have been visited
que.offer(adjVet); // Only enqueue unvisited vertices
continue; // Skip vertices that have already been visited
que.offer(adjVet); // Enqueue only unvisited vertices
visited.add(adjVet); // Mark this vertex as visited
}
}
// Return vertex traversal sequence
// Return the vertex traversal sequence
return res;
}
public static void main(String[] args) {
/* Add edge */
/* Initialize the undirected graph */
Vertex[] v = Vertex.valsToVets(new int[] { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 });
Vertex[][] edges = { { v[0], v[1] }, { v[0], v[3] }, { v[1], v[2] }, { v[1], v[4] },
{ v[2], v[5] }, { v[3], v[4] }, { v[3], v[6] }, { v[4], v[5] },
{ v[4], v[7] }, { v[5], v[8] }, { v[6], v[7] }, { v[7], v[8] } };
GraphAdjList graph = new GraphAdjList(edges);
System.out.println("\nAfter initialization, graph is");
System.out.println("\nGraph after initialization:");
graph.print();
/* Breadth-first traversal */
List<Vertex> res = graphBFS(graph, v[0]);
System.out.println("\nBreadth-first traversal (BFS) vertex sequence is");
System.out.println("\nVertex sequence from breadth-first traversal (BFS):");
System.out.println(Vertex.vetsToVals(res));
}
}

18
en/codes/java/chapter_graph/graph_dfs.java
View File

@@ -12,40 +12,40 @@ import utils.*;
public class graph_dfs {
/* Depth-first traversal helper function */
static void dfs(GraphAdjList graph, Set<Vertex> visited, List<Vertex> res, Vertex vet) {
res.add(vet); // Record visited vertex
res.add(vet); // Record the visited vertex
visited.add(vet); // Mark this vertex as visited
// Traverse all adjacent vertices of this vertex
// Traverse all neighbors of this vertex
for (Vertex adjVet : graph.adjList.get(vet)) {
if (visited.contains(adjVet))
continue; // Skip vertices that have been visited
// Recursively visit adjacent vertices
continue; // Skip vertices that have already been visited
// Recursively visit the neighboring vertex
dfs(graph, visited, res, adjVet);
}
}
/* Depth-first traversal */
// Use adjacency list to represent the graph, in order to obtain all adjacent vertices of a specified vertex
// Represent the graph with an adjacency list to access all neighbors of a given vertex
static List<Vertex> graphDFS(GraphAdjList graph, Vertex startVet) {
// Vertex traversal sequence
List<Vertex> res = new ArrayList<>();
// Hash set for recording vertices that have been visited
// Hash set recording visited vertices
Set<Vertex> visited = new HashSet<>();
dfs(graph, visited, res, startVet);
return res;
}
public static void main(String[] args) {
/* Add edge */
/* Initialize the undirected graph */
Vertex[] v = Vertex.valsToVets(new int[] { 0, 1, 2, 3, 4, 5, 6 });
Vertex[][] edges = { { v[0], v[1] }, { v[0], v[3] }, { v[1], v[2] },
{ v[2], v[5] }, { v[4], v[5] }, { v[5], v[6] } };
GraphAdjList graph = new GraphAdjList(edges);
System.out.println("\nAfter initialization, graph is");
System.out.println("\nGraph after initialization:");
graph.print();
/* Depth-first traversal */
List<Vertex> res = graphDFS(graph, v[0]);
System.out.println("\nDepth-first traversal (DFS) vertex sequence is");
System.out.println("\nVertex sequence from depth-first traversal (DFS):");
System.out.println(Vertex.vetsToVals(res));
}
}