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POHow to reverse an array of strings recursively?
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copied!<p>supposed to reverse an array of strings recursively.</p> <p>having trouble implementing this. if i was using a for loop i would just start it at the end of the array and print out the array starting with the last element and ending with the first.</p> <p>I'm not too sure how to do it recursively. i was thinking about using a swap but that idea sort of fizzled when i couldnt figure out how to change the elements that i was swapping.</p> <p>any ideas or a push in the right direction would be appreciated.</p> <hr> <p>this is what icame up with so far. i know its wrong, i get an error out of bounds exception which im not sure how to fix. I think im not swapping the first and last correctly. but am i getting the right idea?</p> <p>this is what i came up with. a is an array. its inside a class.</p> <pre><code>// reverse an array public void rev() { rev(0,a.length-1); } private void rev(int first, int last) { if(last == 0) { //do nothing } else { while(first != last) { int temp = first; first = last; last = temp; System.out.print(" " + a[first]); rev((first + 1), (last - 1)); } } } </code></pre> <hr> <p>made some changes and it reverses the last 3 elements but the it repeats the second element. i have no if statement that controls when it runs so shouldnt it run until left = right?</p> <p>this is what i changed it to</p> <pre><code>// reverse an array public void rev() { rev(0,a.length-1); } private void rev(int first, int last) { if(last == 0) { //do nothing } else { String temp = a[first]; a[first] = a[last]; a[last] = temp; System.out.print(" " + a[first]); rev(first+ 1, last-1); } } </code></pre>

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