Update 09.2.md: 修复代码缩减问题 (#810)

Co-authored-by: qiujinfeng <[email protected]>

eBook/09.2.md

@@ -22,23 +22,25 @@ ok, _ := regexp.MatchString(pat, searchIn)
 
 ```go
 package main
+
 import (
 	"fmt"
 	"regexp"
 	"strconv"
 )
+
 func main() {
 	//目标字符串
 	searchIn := "John: 2578.34 William: 4567.23 Steve: 5632.18"
 	pat := "[0-9]+.[0-9]+" //正则
 
-	f := func(s string) string{
-    	v, _ := strconv.ParseFloat(s, 32)
-    	return strconv.FormatFloat(v * 2, 'f', 2, 32)
+	f := func(s string) string {
+		v, _ := strconv.ParseFloat(s, 32)
+		return strconv.FormatFloat(v*2, 'f', 2, 32)
 	}
 
 	if ok, _ := regexp.Match(pat, []byte(searchIn)); ok {
-    fmt.Println("Match Found!")
+		fmt.Println("Match Found!")
 	}
 
 	re, _ := regexp.Compile(pat)