[Add Example] See who doesn't follow back

examples/user/seeunfollowers.go

@@ -0,0 +1,70 @@
+// +build ignore
+
+package main
+
+import (
+	"fmt"
+	"os"
+	"strings"
+
+	e "github.com/ahmdrz/goinsta/examples"
+)
+
+func main() {
+	var followers []string
+	var followings []string
+	inst, err := e.InitGoinsta("<target user>")
+	e.CheckErr(err)
+
+	user, err := inst.Profiles.ByName(os.Args[0])
+	e.CheckErr(err)
+
+	users_following := user.Following()
+	e.CheckErr(err)
+
+	users_follower := user.Followers()
+	e.CheckErr(err)
+
+	// collect usernames from Instagram following section
+	following_counter := 1
+	for users_following.Next() {
+		for _, user := range users_following.Users {
+			following_counter++
+			followings = append(followings, user.Username)
+		}
+	}
+
+	// collect usernames from Instagram followers section
+	follower_counter := 1
+	for users_follower.Next() {
+		for _, user := range users_follower.Users {
+			follower_counter++
+			followers = append(followers, user.Username)
+		}
+	}
+
+	fmt.Println("\nTOTAL FOLLOWING:", following_counter)
+	fmt.Println("TOTAL FOLLOWER:", follower_counter)
+	fmt.Println("TOTAL DOESN'T FOLLOW YOU BACK:", len(differ(followings, followers)))
+	fmt.Println("WHO DOESN'T FOLLOW YOU BACK:\n", strings.Trim(fmt.Sprint(differ(followings, followers)), "[]"))
+
+	if !e.UsingSession {
+		err = inst.Logout()
+		e.CheckErr(err)
+	}
+}
+
+func differ(a, b []string) (diff []string) {
+	m := make(map[string]bool)
+
+	for _, item := range b {
+		m[item] = true
+	}
+
+	for _, item := range a {
+		if _, ok := m[item]; !ok {
+			diff = append(diff, item)
+		}
+	}
+	return
+}