编辑代码

var myString = "Hello world!     -  swift.jsrun.net"
print(myString)
func display(){
for i in O..<rows {
forj in 0..<cols{
// 字符间有一个空格,这样就容易区分
print(group[i*cols+j], separator:" ", terminator:"")
}
// 输出一个空行
print()
}
}