package main import (  "fmt"  "crypto/md5"  "encoding/base64"  "time" ) var cipher = "密鑰" var h = md5.New() func cipherEncode(sourceText string) string {   h.Write([]byte(cipher))  cipherHash := fmt.Sprintf("%x", h.Sum(nil))  h.Reset()  inputData := []byte(sourceText)  loopCount := len(inputData)  outData := make([]byte,loopCount)  for i:= 0; i < loopCount ; i++ {   outData[i] = inputData[i] ^ cipherHash[i%32]  }   return fmt.Sprintf("%s", outData) } func encode(sourceText string) string {   h.Write([]byte(time.Now().Format("2006-01-02 15:04:05")))  noise := fmt.Sprintf("%x", h.Sum(nil))  h.Reset()  inputData := []byte(sourceText)  loopCount := len(inputData)  outData := make([]byte,loopCount*2)    for i, j := 0,0; i < loopCount ; i,j = i+1,j+1 {     outData[j] = noise[i%32]   j++   outData[j] = inputData[i] ^ noise[i%32]  }    return base64.StdEncoding.EncodeToString([]byte(cipherEncode(fmt.Sprintf("%s", outData)))) } func decode(sourceText string) string {  buf, err := base64.StdEncoding.DecodeString(sourceText)  if err != nil {   fmt.Println("Decode(%q) failed: %v", sourceText, err)   return ""  }  inputData := []byte(cipherEncode(fmt.Sprintf("%s", buf)))  loopCount := len(inputData)  outData := make([]byte,loopCount)  for i, j := 0,0; i < loopCount ; i,j = i+2,j+1 {     outData[j] = inputData[i] ^ inputData[i+1]  }  return fmt.Sprintf("%s", outData) } func main() {         s := encode("張學友")  fmt.Println(s)  fmt.Println(decode(s)) }