我有以下功能,它反转字符串值的显示顺序.我是Swift的新手,我试图理解它的逻辑.'!pleh'值的变化是什么变成了'帮助!' ？谢谢
func reverse(_ s: String) -> String {
var str = ""
for character in s.characters {
str = "\(character)" + str
}
return str
}
print (reverse("!pleH"))