fun main(){
    val x = readLine()!!.toInt()
    var i = 0
    while (i < x) {
        var j = 0
        while (j < x) {
            if (i == 0 || i == x-1){
                print("*")
            }
            else{
                if (j == 0 || j == x - 1){
                    print("*")
                }
                else
                    print(" ")
            }
            j++
        }
        println()
        i++
    }
}