feat:add golang solution for lcof problem 06 07 09

lcof/面试题06. 从尾到头打印链表/README.md

@@ -60,9 +60,24 @@ class Solution {
 }
 ```
 
-### JavaScript
-```js
-
+### Go
+```go
+/**
+ * Definition for singly-linked list.
+ * type ListNode struct {
+ *     Val int
+ *     Next *ListNode
+ * }
+ */
+ //insert to the front
+func reversePrint(head *ListNode) []int {
+    res := []int{}
+    for head != nil {
+        res = append([]int{head.Val}, res...)
+        head = head.Next
+    }
+    return res
+}
 ```
 
 ### ...

lcof/面试题06. 从尾到头打印链表/Solution.go

@@ -0,0 +1,16 @@
+/**
+ * Definition for singly-linked list.
+ * type ListNode struct {
+ *     Val int
+ *     Next *ListNode
+ * }
+ */
+ //insert to the front
+func reversePrint(head *ListNode) []int {
+    res := []int{}
+    for head != nil {
+        res = append([]int{head.Val}, res...)
+        head = head.Next
+    }
+    return res
+}

lcof/面试题07. 重建二叉树/README.md

@@ -136,7 +136,40 @@ var buildTree = function(preorder, inorder) {
 };
 ```
 
+### Go
+
+```go
+/**
+ * Definition for a binary tree node.
+ * type TreeNode struct {
+ *     Val int
+ *     Left *TreeNode
+ *     Right *TreeNode
+ * }
+ */
+func buildTree(preorder []int, inorder []int) *TreeNode {
+    return helper(preorder, inorder, 0, 0, len(preorder)-1)
+}
+
+func helper(preorder, inorder []int, index, start, end int) *TreeNode {
+    if start > end {
+        return nil
+    }
+    root := &TreeNode{Val:preorder[index]}
+    j := start
+    for j < end && preorder[index] != inorder[j] {
+        j++
+    }
+    root.Left = helper(preorder, inorder, index + 1, start, j - 1)
+    root.Right = helper(preorder, inorder, index + 1 + j -start, j + 1, end)
+    return root
+}
+```
+
+
+
 ### ...
+
 ```
 
 ```

lcof/面试题07. 重建二叉树/Solution.go

@@ -0,0 +1,25 @@
+/**
+ * Definition for a binary tree node.
+ * type TreeNode struct {
+ *     Val int
+ *     Left *TreeNode
+ *     Right *TreeNode
+ * }
+ */
+func buildTree(preorder []int, inorder []int) *TreeNode {
+    return helper(preorder, inorder, 0, 0, len(preorder)-1)
+}
+
+func helper(preorder, inorder []int, index, start, end int) *TreeNode {
+    if start > end {
+        return nil
+    }
+    root := &TreeNode{Val:preorder[index]}
+    j := start
+    for j < end && preorder[index] != inorder[j] {
+        j++
+    }
+    root.Left = helper(preorder, inorder, index + 1, start, j - 1)
+    root.Right = helper(preorder, inorder, index + 1 + j -start, j + 1, end)
+    return root
+}

lcof/面试题09. 用两个栈实现队列/README.md

@@ -124,7 +124,49 @@ CQueue.prototype.deleteHead = function() {
 };
 ```
 
+### Go
+
+```go
+type CQueue struct {
+    Stack1 []int
+    Stack2 []int
+}
+// 入队都往S1压入，弹出时判定S2是否为空，S2非空则弹出S2顶
+//否则，S1的元素从栈顶依次入S2,再从S2弹出
+
+func Constructor() CQueue {
+    return CQueue{Stack1:[]int{},Stack2:[]int{}}
+}
+
+
+func (this *CQueue) AppendTail(value int)  {
+    this.Stack1 = append(this.Stack1, value)
+}
+
+
+func (this *CQueue) DeleteHead() int {
+    if len(this.Stack1) == 0 && len(this.Stack2) == 0 {
+        return -1
+    }
+    if len(this.Stack2) > 0 {
+        res := this.Stack2[len(this.Stack2)-1]
+        this.Stack2 = this.Stack2[0:len(this.Stack2)-1]
+        return res
+    }
+    for len(this.Stack1) > 0 {
+        this.Stack2 = append(this.Stack2,this.Stack1[len(this.Stack1)-1])
+        this.Stack1 = this.Stack1[0:len(this.Stack1)-1]
+    }
+    res := this.Stack2[len(this.Stack2)-1]
+    this.Stack2 = this.Stack2[0:len(this.Stack2)-1]
+    return res
+}
+```
+
+
+
 ### ...
+
 ```
 
 ```

lcof/面试题09. 用两个栈实现队列/Solution.go

@@ -0,0 +1,34 @@
+type CQueue struct {
+    Stack1 []int
+    Stack2 []int
+}
+// 入队都往S1压入，弹出时判定S2是否为空，S2非空则弹出S2顶，否则，S1的元素从栈顶依次入S2
+//再从S2弹出
+
+func Constructor() CQueue {
+    return CQueue{Stack1:[]int{},Stack2:[]int{}}
+}
+
+
+func (this *CQueue) AppendTail(value int)  {
+    this.Stack1 = append(this.Stack1, value)
+}
+
+
+func (this *CQueue) DeleteHead() int {
+    if len(this.Stack1) == 0 && len(this.Stack2) == 0 {
+        return -1
+    }
+    if len(this.Stack2) > 0 {
+        res := this.Stack2[len(this.Stack2)-1]
+        this.Stack2 = this.Stack2[0:len(this.Stack2)-1]
+        return res
+    }
+    for len(this.Stack1) > 0 {
+        this.Stack2 = append(this.Stack2,this.Stack1[len(this.Stack1)-1])
+        this.Stack1 = this.Stack1[0:len(this.Stack1)-1]
+    }
+    res := this.Stack2[len(this.Stack2)-1]
+    this.Stack2 = this.Stack2[0:len(this.Stack2)-1]
+    return res
+}