Merge pull request #188 from Cathay-Chen/master

Add the Go code to array and linked_list docs (Chapter of Array and LinkedList)
krahets · Jan 2, 2023 · fd4737e · fd4737e
2 parents 5ea660a + 82b8a5d
commit fd4737e
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diff --git a/codes/go/chapter_array_and_linkedlist/array.go b/codes/go/chapter_array_and_linkedlist/array.go
@@ -1,6 +1,6 @@
 // File: array.go
 // Created Time: 2022-12-29
-// Author: GuoWei (gongguowei01@gmail.com)
+// Author: GuoWei (gongguowei01@gmail.com), cathay (cathaycchen@gmail.com)
 
 package chapter_array_and_linkedlist
 
@@ -38,7 +38,6 @@ func extend(nums []int, enlarge int) []int {
 /* 在数组的索引 index 处插入元素 num */
 func insert(nums []int, num int, index int) {
 	// 把索引 index 以及之后的所有元素向后移动一位
-	// 如果超出了数组长度，会被直接舍弃
 	for i := len(nums) - 1; i > index; i-- {
 		nums[i] = nums[i-1]
 	}
@@ -49,14 +48,14 @@ func insert(nums []int, num int, index int) {
 /* 删除索引 index 处元素 */
 func remove(nums []int, index int) {
 	// 把索引 index 之后的所有元素向前移动一位
-	for i := index; i < len(nums) - 1; i++ {
+	for i := index; i < len(nums)-1; i++ {
 		nums[i] = nums[i+1]
 	}
 }
 
 /* 遍历数组 */
 func traverse(nums []int) {
-	var count int
+	count := 0
 	// 通过索引遍历数组
 	for i := 0; i < len(nums); i++ {
 		count++

diff --git a/codes/go/chapter_array_and_linkedlist/array_test.go b/codes/go/chapter_array_and_linkedlist/array_test.go
@@ -1,6 +1,6 @@
 // File: array_test.go
 // Created Time: 2022-12-29
-// Author: GuoWei (gongguowei01@gmail.com)
+// Author: GuoWei (gongguowei01@gmail.com), cathay (cathaycchen@gmail.com)
 
 package chapter_array_and_linkedlist
 
@@ -18,30 +18,30 @@ import (
 func TestArray(t *testing.T) {
 	/* 初始化数组 */
 	var arr []int
-	fmt.Println("数组 arr = ", arr)
+	fmt.Println("数组 arr =", arr)
 	nums := []int{1, 3, 2, 5, 4}
-	fmt.Println("数组 nums = ", nums)
+	fmt.Println("数组 nums =", nums)
 
 	/* 随机访问 */
 	randomNum := randomAccess(nums)
-	fmt.Println("在 nums 中获取随机元素 ", randomNum)
+	fmt.Println("在 nums 中获取随机元素", randomNum)
 
 	/* 长度扩展 */
 	nums = extend(nums, 3)
-	fmt.Println("将数组长度扩展至 8 ，得到 nums = ", nums)
+	fmt.Println("将数组长度扩展至 8 ，得到 nums =", nums)
 
 	/* 插入元素 */
 	insert(nums, 6, 3)
-	fmt.Println("在索引 3 处插入数字 6 ，得到 nums = ", nums)
+	fmt.Println("在索引 3 处插入数字 6 ，得到 nums =", nums)
 
 	/* 删除元素 */
 	remove(nums, 2)
-	fmt.Println("删除索引 2 处的元素，得到 nums = ", nums)
+	fmt.Println("删除索引 2 处的元素，得到 nums =", nums)
 
 	/* 遍历数组 */
 	traverse(nums)
 
 	/* 查找元素 */
 	index := find(nums, 3)
-	fmt.Println("在 nums 中查找元素 3 ，得到索引 = ", index)
+	fmt.Println("在 nums 中查找元素 3 ，得到索引 =", index)
 }
diff --git a/codes/go/chapter_array_and_linkedlist/linked_list.go b/codes/go/chapter_array_and_linkedlist/linked_list.go
@@ -0,0 +1,51 @@
+// File: linked_list.go
+// Created Time: 2022-12-29
+// Author: cathay (cathaycchen@gmail.com)
+
+package chapter_array_and_linkedlist
+
+import (
+	. "github.com/krahets/hello-algo/pkg"
+)
+
+/* 在链表的结点 n0 之后插入结点 P */
+func insertNode(n0 *pkg.ListNode, P *pkg.ListNode) {
+	n1 := n0.Next
+	n0.Next = P
+	P.Next = n1
+}
+
+/* 删除链表的结点 n0 之后的首个结点 */
+func removeNode(n0 *pkg.ListNode) {
+	if n0.Next == nil {
+		return
+	}
+	// n0 -> P -> n1
+	P := n0.Next
+	n1 := P.Next
+	n0.Next = n1
+}
+
+/* 访问链表中索引为 index 的结点 */
+func access(head *pkg.ListNode, index int) *pkg.ListNode {
+	for i := 0; i < index; i++ {
+		head = head.Next
+		if head == nil {
+			return nil
+		}
+	}
+	return head
+}
+
+/* 在链表中查找值为 target 的首个结点 */
+func findNode(head *pkg.ListNode, target int) int {
+	index := 0
+	for head != nil {
+		if head.Val == target {
+			return index
+		}
+		head = head.Next
+		index++
+	}
+	return -1
+}
diff --git a/codes/go/chapter_array_and_linkedlist/linked_list_test.go b/codes/go/chapter_array_and_linkedlist/linked_list_test.go
@@ -0,0 +1,47 @@
+// File: linked_list_test.go
+// Created Time: 2022-12-29
+// Author: cathay (cathaycchen@gmail.com)
+
+package chapter_array_and_linkedlist
+
+import (
+	"fmt"
+	"github.com/krahets/hello-algo/pkg"
+	"testing"
+)
+
+func TestLikedList(t *testing.T) {
+	/* 初始化链表 1 -> 3 -> 2 -> 5 -> 4 */
+	// 初始化各个结点
+	n0 := pkg.NewListNode(1)
+	n1 := pkg.NewListNode(3)
+	n2 := pkg.NewListNode(2)
+	n3 := pkg.NewListNode(5)
+	n4 := pkg.NewListNode(4)
+
+	// 构建引用指向
+	n0.Next = n1
+	n1.Next = n2
+	n2.Next = n3
+	n3.Next = n4
+	fmt.Println("初始化的链表为")
+	pkg.PrintLinkedList(n0)
+
+	/* 插入结点 */
+	insertNode(n0, pkg.NewListNode(0))
+	fmt.Println("插入结点后的链表为")
+	pkg.PrintLinkedList(n0)
+
+	/* 删除结点 */
+	removeNode(n0)
+	fmt.Println("删除结点后的链表为")
+	pkg.PrintLinkedList(n0)
+
+	/* 访问结点 */
+	node := access(n0, 3)
+	fmt.Println("链表中索引 3 处的结点的值 =", node)
+
+	/* 查找结点 */
+	index := findNode(n0, 2)
+	fmt.Println("链表中值为 2 的结点的索引 =", index)
+}
diff --git a/docs/chapter_array_and_linkedlist/array.md b/docs/chapter_array_and_linkedlist/array.md
@@ -250,8 +250,8 @@ elementAddr = firtstElementAddr + elementLength * elementIndex
         // 初始化一个扩展长度后的数组
         res := make([]int, len(nums)+enlarge)
         // 将原数组中的所有元素复制到新数组
-        for i := 0; i < len(nums); i++ {
-            res[i] = nums[i]
+        for i, num := range nums {
+            res[i] = num
         }
         // 返回扩展后的新数组
         return res
@@ -537,14 +537,14 @@ elementAddr = firtstElementAddr + elementLength * elementIndex
     ```go title="array.go"
     /* 遍历数组 */
     func traverse(nums []int) {
-        var count int
+        count := 0
         // 通过索引遍历数组
         for i := 0; i < len(nums); i++ {
             count++
         }
         // 直接遍历数组
-        for index, val := range nums {
-            fmt.Printf("index:%v value:%v\n", index, val)
+        for range nums {
+            count++
         }
     }
     ```

diff --git a/docs/chapter_array_and_linkedlist/linked_list.md b/docs/chapter_array_and_linkedlist/linked_list.md
@@ -51,7 +51,19 @@ comments: true
 === "Go"
 
     ```go title=""
-
+    /* 链表结点结构体 */
+    type ListNode struct {
+        Val  int       // 结点值
+        Next *ListNode // 指向下一结点的指针（引用）
+    }
+
+    // NewListNode 构造函数，创建一个新的链表
+    func NewListNode(val int) *ListNode {
+        return &ListNode{
+            Val:  val,
+            Next: nil,
+        }
+    }
     ```
 
 === "JavaScript"
@@ -162,7 +174,19 @@ comments: true
 === "Go"
 
     ```go title=""
-
+    /* 初始化链表 1 -> 3 -> 2 -> 5 -> 4 */
+    // 初始化各个结点
+    n0 := NewListNode(1)
+    n1 := NewListNode(3)
+    n2 := NewListNode(2)
+    n3 := NewListNode(5)
+    n4 := NewListNode(4)
+
+    // 构建引用指向
+    n0.Next = n1
+    n1.Next = n2
+    n2.Next = n3
+    n3.Next = n4
     ```
 
 === "JavaScript"
@@ -294,7 +318,23 @@ comments: true
 === "Go"
 
     ```go title=""
+    /* 在链表的结点 n0 之后插入结点 P */
+    func insert(n0 *ListNode, P *ListNode) {
+        n1 := n0.Next
+        n0.Next = P
+        P.Next = n1
+    }
 
+    /* 删除链表的结点 n0 之后的首个结点 */
+    func removeNode(n0 *ListNode) {
+        if n0.Next == nil {
+            return
+        }
+        // n0 -> P -> n1
+        P := n0.Next
+        n1 := P.Next
+        n0.Next = n1
+    }
     ```
 
 === "JavaScript"
@@ -415,7 +455,16 @@ comments: true
 === "Go"
 
     ```go title=""
-
+    /* 访问链表中索引为 index 的结点 */
+    func access(head *ListNode, index int) *ListNode {
+        for i := 0; i < index; i++ {
+            head = head.Next
+            if head == nil {
+                return nil
+            }
+        }
+        return head
+    }
     ```
 
 === "JavaScript"
@@ -524,7 +573,18 @@ comments: true
 === "Go"
 
     ```go title=""
-
+    /* 在链表中查找值为 target 的首个结点 */
+    func find(head *ListNode, target int) int {
+        index := 0
+        for head != nil {
+            if head.Val == target {
+                return index
+            }
+            head = head.Next
+            index++
+        }
+        return -1
+    }
     ```
 
 === "JavaScript"
@@ -631,7 +691,21 @@ comments: true
 === "Go"
 
     ```go title=""
-
+    /* 双向链表结点结构体 */
+    type DoublyListNode struct {
+        Val  int             // 结点值
+        Next *DoublyListNode // 指向后继结点的指针（引用）
+        Prev *DoublyListNode // 指向前驱结点的指针（引用）
+    }
+
+    // NewDoublyListNode 初始化
+    func NewDoublyListNode(val int) *DoublyListNode {
+        return &DoublyListNode{
+            Val:  val,
+            Next: nil,
+            Prev: nil,
+        }
+    }
     ```
 
 === "JavaScript"