Question

Write a recursive method called repeat that accepts a string s and an integer n as parameters and that returns s concatenated together n times. For example, repeat("hello", 3) returns "hellohellohello", and repeat("ok", 1) returns "ok", and repeat("bye", 0) returns "". String concatenation is an expensive operation, so for an added challenge try to solve this problem while performing fewer than n concatenations.

Answer 1

Answer:

public static String repeat(String text, int repeatCount) {

   if(repeatCount < 0) {

       throw new IllegalArgumentException("repeat count should be either 0 or a positive value");

   }

   if(repeatCount == 0) {

       return "";

   } else {

       return text + repeat(text, repeatCount-1);

   }

}

Explanation:

Here repeatCount is an int value.

at first we will check if repeatCount is non negative number and if it is code will throw exception.

If the value is 0 then we will return ""

If the value is >0 then recursive function is called again untill the repeatCount value is 0.