From dee606e6ab14096da1c1f079dad367cfeb33898f Mon Sep 17 00:00:00 2001
From: sre <sre@yangqiao.org>
Date: Wed, 22 Jun 2022 18:47:56 +0800
Subject: [PATCH] =?UTF-8?q?62=E8=BF=9B=E5=88=B6=E6=95=B0=E5=AD=97=E8=BD=AC?=
 =?UTF-8?q?=E6=8D=A2?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 str/bit62.go      | 41 +++++++++++++++++++++++++++++++++++++++++
 str/bit62_test.go | 31 +++++++++++++++++++++++++++++++
 str/entry.go      |  4 ++++
 str/entry_test.go |  3 +++
 str/str.go        |  3 ---
 str/str_test.go   |  2 --
 6 files changed, 79 insertions(+), 5 deletions(-)
 create mode 100644 str/bit62.go
 create mode 100644 str/bit62_test.go
 create mode 100644 str/entry.go
 create mode 100644 str/entry_test.go

diff --git a/str/bit62.go b/str/bit62.go
new file mode 100644
index 0000000..da9a1ac
--- /dev/null
+++ b/str/bit62.go
@@ -0,0 +1,41 @@
+package str
+
+import (
+	"math"
+	"strings"
+)
+
+var Bit62Chars string = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
+
+// 翻转[]byte
+func ByteReverse(a []byte) {
+	for left, right := 0, len(a)-1; left < right; left, right = left+1, right-1 {
+		a[left], a[right] = a[right], a[left]
+	}
+}
+
+// int64 -> string
+func (s *Str) Bit62Encode(num int64) string {
+	bytes := []byte{}
+	for num > 0 {
+		bytes = append(bytes, Bit62Chars[num%62])
+		num = num / 62
+	}
+	ByteReverse(bytes)
+	return string(bytes)
+}
+
+// string -> int64
+func (s *Str) Bit62Decode(str string) int64 {
+	var num int64
+	n := len(str)
+	for i := 0; i < n; i++ {
+		pos := strings.IndexByte(Bit62Chars, str[i])
+		num += int64(math.Pow(62, float64(n-i-1)) * float64(pos))
+	}
+	return num
+}
+
+func (s *Str) Bit62Add(base, value string) string {
+	return s.Bit62Encode(s.Bit62Decode(base) + s.Bit62Decode(value))
+}
diff --git a/str/bit62_test.go b/str/bit62_test.go
new file mode 100644
index 0000000..a4699f4
--- /dev/null
+++ b/str/bit62_test.go
@@ -0,0 +1,31 @@
+package str
+
+import (
+	"fmt"
+	"testing"
+)
+
+func TestReverse(tt *testing.T) {
+	a := []byte("hello world")
+	fmt.Println(a)
+	//[104 101 108 108 111 32 119 111 114 108 100]
+	ByteReverse(a)
+	fmt.Println(a)
+	//[100 108 114 111 119 32 111 108 108 101 104]
+
+}
+
+func TestBit62Add(t *testing.T) {
+	var num int64 = 1234567890
+	var num1 int64 = 5
+	numB62 := StrTool.Bit62Encode(num)
+	num1B62 := StrTool.Bit62Encode(num1)
+	fmt.Println(numB62)
+	fmt.Println(num1B62)
+	num2B62 := StrTool.Bit62Add(numB62, num1B62)
+	num2 := StrTool.Bit62Decode(num2B62)
+	fmt.Println(num2B62)
+	fmt.Println(num2)
+	fmt.Println(StrTool.Bit62Add("ly7vp", "1"))
+
+}
diff --git a/str/entry.go b/str/entry.go
new file mode 100644
index 0000000..595166b
--- /dev/null
+++ b/str/entry.go
@@ -0,0 +1,4 @@
+package str
+
+type Str struct {
+}
diff --git a/str/entry_test.go b/str/entry_test.go
new file mode 100644
index 0000000..7349b1e
--- /dev/null
+++ b/str/entry_test.go
@@ -0,0 +1,3 @@
+package str
+
+var StrTool Str
diff --git a/str/str.go b/str/str.go
index 95b1ec3..bc80611 100644
--- a/str/str.go
+++ b/str/str.go
@@ -2,9 +2,6 @@ package str
 
 import "encoding/hex"
 
-type Str struct {
-}
-
 // struing to hex
 func (s *Str) HexEncode(str string) string {
 	byteStr := []byte(str)
diff --git a/str/str_test.go b/str/str_test.go
index 7959170..e996a75 100644
--- a/str/str_test.go
+++ b/str/str_test.go
@@ -5,8 +5,6 @@ import (
 	"testing"
 )
 
-var StrTool Str
-
 func TestHexEncode(t *testing.T) {
 	fmt.Println(StrTool.HexEncode("hello world!"))
 	//68656c6c6f20776f726c6421