Is it possible to print a string 'x' times?
For example if given the string
String q = "*"; Let's say the user entered the number '4' for the amount of times that they wanted the string repeated.
The program would print:
**** 
- 8You can use recursion.Rahul– Rahul2013-10-18 17:19:35 +00:00Commented Oct 18, 2013 at 17:19
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6 Answers
You can use recursion like this
private void printStar(int n){ if(n > 0){ System.out.print("*"); printStar(n-1); } } And call the method like this initially - printStar(4);
You can make use of a char[] array of given length to build a String, then replace each character with *:
String repeatedStar = new String(new char[4]).replace('\0', '*'); Well, that would use a loop internally though.
1 Comment
From the Apache commons common-lang, use StringUtils.repeat:
System.out.println(StringUtils.repeat(q,4)); Comments
Although it probably loops internally, you could use Guava's Strings avoiding loops in the user code:
System.out.println(Strings.repeat("*", 4)); 
In recursion
printStar(int x) { if(x > 0) { System.out.print("*"); printStar(x-1); } } 
Comments
I know the point is probably to use recursion, but recursion in this case is a horrible solution. Here's a solution that is more efficient (though it very likely uses a loop in Arrays.fill!)
public static void printNX(int n) { char[] c = new char[n]; Arrays.fill(c, 'x'); System.out.println(new String(c)); } Of course, it's possible that Arrays.fill is calls into native code which is optimized to use an efficient instruction for filling the array and avoids a loop. But you never know.
I don't necessarily agree that using recursion "isn't looping"; all this is doing is thrashing the stack; the the CPU will still technically loop by continually jumping back to the top of the recursive function.
