'天降字符串转整数'

BinarySearch/main.go

@@ -4,7 +4,7 @@
  * @Autor: zhuyijun
  * @Date: 2021-03-29 09:08:50
  * @LastEditors: zhuyijun
- * @LastEditTime: 2021-03-29 17:35:47
+ * @LastEditTime: 2021-03-30 08:59:23
  */
 package main
 
@@ -14,20 +14,110 @@ import "fmt"
 二分查找算法
 */
 func BinarySearch(key int, a []int) int {
-	lo := 0
+	start := 0
-	hi := len(a) - 1
+	end := len(a) - 1
-	for lo < hi {
+	for start < end {
-		mid := lo + (hi-lo)/2
+		mid := start + ((end - start) >> 1)
 		if key < a[mid] {
-			hi = mid - 1
+			end = mid - 1
 		} else if key > a[mid] {
-			lo = mid + 1
+			start = mid + 1
 		} else {
 			return mid
 		}
 	}
 	return -1
 }
+
+//查找第一个值等于给定值得元素
+func BinarySearch2(nums []int, value int) int {
+	length := len(nums)
+	start := 0
+	end := length - 1
+	for start <= end {
+		mid := start + ((end - start) >> 1)
+		if nums[mid] > value {
+			end = mid - 1
+		} else if nums[mid] < value {
+			start = mid + 1
+		} else {
+			for mid >= 0 {
+				if nums[mid-1] == value {
+					mid--
+				} else {
+					return mid
+				}
+			}
+		}
+	}
+	return -1
+}
+
+// 查找最后一个值等于给定值的元素
+func BinarySearch3(nums []int, value int) int {
+	start := 0
+	end := len(nums) - 1
+	for start <= end {
+		mid := start + ((end - start) >> 1)
+		if nums[mid] > value {
+			end = mid - 1
+		} else if nums[mid] < value {
+			start = mid + 1
+		} else {
+			for mid < len(nums) {
+				if nums[mid+1] == value {
+					mid++
+				} else {
+					return mid
+				}
+			}
+		}
+	}
+	return -1
+}
+
+// 查找第一个大于等于给定值的元素
+func BinarySearch4(nums []int, value int) int {
+	start := 0
+	end := len(nums) - 1
+	for start <= end {
+		mid := (start + end) >> 1
+		if nums[mid] < value {
+			start = mid + 1
+		} else {
+			for mid >= 0 {
+				if nums[mid-1] >= value {
+					mid--
+				} else {
+					return mid
+				}
+			}
+		}
+	}
+	return -1
+}
+
+// 查找最后一个小于等于给定值的元素
+func BinarySearch5(nums []int, value int) int {
+	start := 0
+	end := len(nums) - 1
+	for start <= end {
+		mid := (start + end) >> 1
+		if nums[mid] > value {
+			end = mid - 1
+		} else {
+			for mid < len(nums) {
+				if nums[mid+1] <= value {
+					mid++
+				} else {
+					return mid
+				}
+			}
+		}
+	}
+	return -1
+}
+
 func main() {
 	var a = []int{0, 2, 4, 7, 9, 11, 45, 67, 99, 100}
 	var i int = 2

DataStructure/array/array.go

@@ -0,0 +1,9 @@
+/*
+ * @Description:
+ * @Version: 2.0
+ * @Autor: zhuyijun
+ * @Date: 2021-03-30 09:01:29
+ * @LastEditors: zhuyijun
+ * @LastEditTime: 2021-03-30 09:01:49
+ */
+package array

leetcode/初级算法/字符串/字符串转换整数 (atoi)/main.go

@@ -0,0 +1,69 @@
+package main
+
+import (
+	"math/big"
+	"strconv"
+)
+
+func myAtoi(s string) int {
+	const MIN int64 = -2147483648
+	const MAX int64 = 2147483647
+	 ret := big.NewInt(0)
+	//正负号
+	flag := true
+	size := len(s)
+	i := 0
+	if s == "" {
+		return 0
+	}
+	//检查空格
+	for ; i < size; i++ {
+		if s[i] != ' ' {
+			break
+		}
+	}
+
+	if i >= size {
+		return 0
+	}
+	//检查正负号;
+	if s[i] == '-' || s[i] == '+' {
+		if s[i] == '-' {
+			flag = false
+		} else {
+			flag = true
+		}
+		i++
+	}
+	//检查数字
+	for ; i < size; i++ {
+		//不是数字就跳出
+		if s[i] > '9' || s[i] < '0' {
+			break
+		} else {
+			n, err := strconv.ParseInt(string(s[i]),10,64)
+			if err != nil {
+				break
+			}
+			ret.Mul(ret,big.NewInt(10))
+			ret.Add(ret,big.NewInt(n))
+		}
+	}
+	//添加符号
+	if flag == false {
+		ret.Neg(ret)
+	}
+
+	if ret.Cmp(big.NewInt(MIN)) < 0 {
+		ret = big.NewInt(MIN)
+	}
+	if ret.Cmp(big.NewInt(MAX)) > 0 {
+		ret = big.NewInt(MAX)
+	}
+
+	return int(ret.Int64())
+}
+
+func main() {
+	print(myAtoi("9223372036854775808"))
+}

leetcode/初级算法/字符串/字符串转换整数 (atoi)/有限状态机/main.go

@@ -0,0 +1,16 @@
+package main
+
+import "strings"
+
+func myAtoi(s string) int {
+	//去除首尾字符
+	s = strings.TrimSpace(s)
+	if len(s) == 0 {
+		return 0
+	}
+	return 0
+}
+
+func main() {
+	print(myAtoi("9223372036854775808"))
+}

leetcode/图解数据结构/06.从头到尾打印链表/main.go

@@ -0,0 +1,102 @@
+/*
+ * @Description:
+ * @Version: 2.0
+ * @Autor: zhuyijun
+ * @Date: 2021-03-31 10:57:16
+ * @LastEditors: zhuyijun
+ * @LastEditTime: 2021-03-31 11:07:30
+ */
+
+/**
+ * Definition for singly-linked list.
+ * type ListNode struct {
+ *     Val int
+ *     Next *ListNode
+ * }
+ */
+package main
+
+import "fmt"
+
+type ListNode struct {
+	Val  int
+	Next *ListNode
+}
+/**
+输入一个链表的头节点，从尾到头反过来返回每个节点的值（用数组返回）。
+
+示例 1：
+输入：head = [1,3,2]
+输出：[2,3,1]
+
+限制：
+
+0 <= 链表长度 <= 10000
+ */
+//方法1 回溯
+func reversePrint(head *ListNode) []int {
+	res := make([]int,0)
+	var reverse func(*ListNode)
+	reverse = func(node *ListNode) {
+		if node.Next != nil {
+			reverse(node.Next)
+		}
+		res = append(res, node.Val)
+	}
+	if head == nil {
+		return nil
+	}
+	reverse(head)
+	return res
+}
+/**
+方法二 一般递归
+ */
+func reversePrint2(head *ListNode) []int {
+	if head == nil {
+		return nil
+	}
+	var nums []int
+	nums = readList(head,nums)
+	len :=len(nums)
+	for  i:= 0; i < len >> 1; i++{
+		temp := nums[i];
+		nums[i] = nums[len - i - 1];
+		nums[len - i - 1] = temp;
+	}
+	return nums
+}
+
+func readList(head *ListNode,nums []int)[]int  {
+	nums = append(nums, head.Val)
+	print(head.Val)
+	if head.Next == nil {
+		return nums
+	}
+	return  readList(head.Next,nums)
+}
+
+/**
+递归回溯
+ */
+func reversePrint3(head *ListNode) []int {
+	if head == nil {
+		return nil
+	}
+	var nums []int
+	readList3(head,&nums)
+	return nums
+}
+
+func readList3(head *ListNode,nums* []int) {
+	if head.Next != nil {
+		readList3(head.Next,nums)
+	}
+	*nums = append(*nums, head.Val)
+}
+
+
+func main() {
+	l := &ListNode{2, &ListNode{1, &ListNode{3, nil}}}
+	fmt.Printf("%v",reversePrint3(l))
+}

leetcode/图解数据结构/09. 用两个栈实现队列/main.go

@@ -0,0 +1,120 @@
+package main
+
+import (
+	"container/list"
+	"fmt"
+)
+
+/*
+用两个栈实现一个队列。队列的声明如下，请实现它的两个函数 appendTail 和 deleteHead ，
+分别完成在队列尾部插入整数和在队列头部删除整数的功能。
+(若队列中没有元素，deleteHead操作返回 -1 )
+
+示例 1：
+输入：
+["CQueue","appendTail","deleteHead","deleteHead"]
+[[],[3],[],[]]
+输出：[null,null,3,-1]
+示例 2：
+输入：
+["CQueue","deleteHead","appendTail","appendTail","deleteHead","deleteHead"]
+[[],[],[5],[2],[],[]]
+输出：[null,-1,null,null,5,2]
+提示：
+1 <= values <= 10000
+最多会对appendTail、deleteHead 进行10000次调用
+
+ */
+type CQueue struct {
+	//入
+	stack1 []int
+	 //出
+	stack2 []int
+
+}
+
+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.stack2) == 0 && len(this.stack1) == 0 {
+		return -1
+	}else if len(this.stack2) == 0 && len(this.stack1) > 0 {
+		l := len(this.stack1) - 1
+		for len(this.stack1) > 0 {
+			val := this.stack1[l]
+			this.stack1 = this.stack1[:l]
+			l--
+			this.stack2 = append(this.stack2,val)
+		}
+	}
+	r := this.stack2[len(this.stack2) - 1]
+	this.stack2 = this.stack2[:len(this.stack2) - 1]
+	return r
+}
+
+
+//方法二
+type CQueue2 struct {
+	stack1, stack2 *list.List
+}
+
+func Constructor2() CQueue2 {
+	return CQueue2{
+		stack1: list.New(),
+		stack2: list.New(),
+	}
+}
+
+func (this *CQueue2) AppendTail2(value int)  {
+	this.stack1.PushBack(value)
+}
+
+func (this *CQueue2) DeleteHead2() int {
+	// 如果第二个栈为空
+	if this.stack2.Len() == 0 {
+		for this.stack1.Len() > 0 {
+			this.stack2.PushBack(this.stack1.Remove(this.stack1.Back()))
+		}
+	}
+	if this.stack2.Len() != 0 {
+		e := this.stack2.Back()
+		this.stack2.Remove(e)
+		return e.Value.(int)
+	}
+	return -1
+}
+
+func main() {
+	obj := Constructor()
+	obj.AppendTail(3)
+	obj.AppendTail(2)
+	obj.AppendTail(3)
+	obj.AppendTail(5)
+	obj.AppendTail(7)
+
+	param_2 := obj.DeleteHead()
+	fmt.Println(param_2)
+
+	param_2 = obj.DeleteHead()
+	fmt.Println(param_2)
+
+	param_2 = obj.DeleteHead()
+	fmt.Println(param_2)
+
+}
+/**
+ * Your CQueue object will be instantiated and called as such:
+ * obj := Constructor();
+ * obj.AppendTail(value);
+ * param_2 := obj.DeleteHead();
+ */
+
+

leetcode/图解数据结构/20. 表示数值的字符串/main.go

@@ -0,0 +1,13 @@
+package main
+
+/**
+请实现一个函数用来判断字符串是否表示数值（包括整数和小数）。
+例如，字符串"+100"、"5e2"、"-123"、"3.1416"、"-1E-16"、"0123"都表示数值，
+但"12e"、"1a3.14"、"1.2.3"、"+-5"及"12e+5.4"都不是。
+*/
+
+
+
+func main() {
+
+}