Hi there, I'm new to this whole site and I was hoping to get some help from anyone with this question please. The question was given to us on a worksheet (and no it is not for an exam) however I have been unable to get into contact with my tutor and this question is really annoying me.

Q) Write a method using the method header below. This method will reverse the elements in an array between a lower index position and an upper index position.

So given the following array declaration

double [] data = {8.5, 12.0, 23.2, 18.0, 15.5, 5.0, 10.5};

following a call to the method Reverse{data, 2, 5); the contents of data would be

{8.5, 12.0, 5.0, 15.5, 18.0, 23.2, 10.5}

You have already written a method called swap that swaps two elements in an array, the elements identified by the two index values passed as parameters.

Swap(array, oneIndex, otherIndex)
public void Reverse( double [] vales, int start, int finish){

That is the question in full, exactly what it says in the same order. I was hoping that I might be able to receive some help on this question as I have having a massively hard time understanding it.
Thanks,
Danb

You need reverse the range given, this can be done by swapping pairs of numbers until the data is reversed. Using your example, you'd swap 2 and 5, 3 and 4 and then you would be done. The following snippet is what you need in your method.

while (start < finish) {
Swap(values, start++, finish--);
}

I Like momerath solution!!!

Be a part of the DaniWeb community

We're a friendly, industry-focused community of developers, IT pros, digital marketers, and technology enthusiasts meeting, networking, learning, and sharing knowledge.