Swift数组下标

var Arr = ["a" , "b" , "c" , "d" , "e" , "f" , "g" ,]
var Brr = ["b" , "d" , "f" , "g" ,]
var gongtong = [Int]()
//print("Arr个数为:\(Arr.count)  Brr个数为:\(Brr.count)")
for  i in 0..<Arr.count{
    for  j in 0..<Brr.count{
        //        print(Arr[i],Brr[j])
        if Arr[i]==Brr[j]{
            gongtong.append(i)
        }
    }
}
print(gongtong)