如何打印由空格分隔n次的相同字符串

Question

I want to make Santa Claus say "Ho" a total of "n" times, where I specify "n". I know how to print it n times, but I don't know how to properly insert a separator between the "Ho"s, such that the result looks like: "Ho Ho Ho"

My attempt at coding this up is given below:

public class Main
{
    public static String repeat(String str, int times) {
        return new String(new char[times]).replace("\0", str);
    }
    public static void main(String[] args) {
        Scanner s=new Scanner(System.in);
        String Ho="Ho";
        int n=s.nextInt();
        System.out.println(repeat(Ho, n)+"!");
    }
}

Answer 1

Since Java 11

We can use String#repeat​(int count) . With it your code can look like

int n = 3;
System.out.println("Ho" + " Ho".repeat(n-1) + "!");
//output: Ho Ho Ho!

Since Java 8

We can use StringJoiner with space as delimiter.

StringJoiner sj = new StringJoiner(" ");
String str = "Ho";
int n = 3;
for (int i = 0; i<n; i++){
    sj.add(str);
}
String text = sj.toString();
System.out.println(text); //Ho Ho Ho

You can also use StringJoiner(delimiter, prefix, suffix) to automatically add ! at the end of joined strings (as suffix);

StringJoiner sj = new StringJoiner(" ","","!");

Answer 2

public class Main {

    public static void main(String[] args) {
        Scanner s = new Scanner(System.in);
        String ho = "Ho";
        int n = s.nextInt();
        System.out.println(repeat(ho, n) + "!");
    }

    public static String repeat(String str, int times) {
        StringBuilder builder=new StringBuilder();
        for(int i=0 ; i<times ; i++){
            builder.append(str).append(" ");
        }
        return builder.toString().trim();
    }
}