ReverseStringRecurse.java

/**
 * Algirithm: reverse string using recursion.
 * Complexity: O(n)
*/
public class ReverseStringRecurse {

    public String reverse(String str) {
       if(str == null || str.length() < 2)
           return str;
       return reverse(str.substring(1)) + str.charAt(0);
    }
}