improved xkcd example

examples/xkcdextract/xkcdextract.go

@@ -2,13 +2,15 @@ package main
 
 import (
 	"fmt"
+
 	"github.com/anaskhan96/soup"
 )
 
 func main() {
-	fmt.Println("Enter the url of the xkcd comic :")
-	var url string
-	fmt.Scanf("%s", &url)
+	fmt.Println("Enter the xkcd comic number :")
+	var num int
+	fmt.Scanf("%d", &num)
+	url := fmt.Sprintf("https://xkcd.com/%d", num)
 	resp, _ := soup.Get(url)
 	doc := soup.HTMLParse(resp)
 	title := doc.Find("div", "id", "ctitle").Text()
@@ -19,8 +21,8 @@ func main() {
 }
 
 /* --- Console I/O ---
-Enter the url of the xkcd comic :
-https://xkcd.com/353
+Enter the xkcd comic number :
+353
 Title of the comic : Python
 Source of the image : //imgs.xkcd.com/comics/python.png
 Underlying text of the image : I wrote 20 short programs in Python yesterday.  It was wonderful.  Perl, I'm leaving you.