Java - Translate the following in-place reverse function from iterative to recur

Question

Java - Translate the following in-place reverse function from iterative to recursive. You should write a helper method. You may not use any "fields" to solve this problem (a field is a variable that is declared "outside" of the function declaration --- either before or after).

public static void reverseI (double[] a) {

       int hi = a.length - 1;

       int lo = 0;

       while (lo < hi) {

           double loVal = a[lo];

           double hiVal = a[hi];

           a[hi] = loVal;

           a[lo] = hiVal;

           lo = lo + 1;

           hi = hi - 1;

       }

   }

Explanation / Answer

Full Program.

import java.util.*;
import java.lang.*;
import java.io.*;
class Reverse{
static void reverse(char s[],int i,int j){
char c;
c = s[i];
s[i] = s[j];
s[j] = c;
i++;
j--;
if(i < j){
reverse(s,i,j);}
else
System.out.println(s);
}
   public static void main (String[] args) throws java.lang.Exception
   {
       String s = "foo bar baz";
       System.out.println(s);
reverse(s.toCharArray(),0,s.length()-1);
   }
}

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