Computer Science

Question

How do i print elements in an array backwards?

Answer 1

You can also use a for loop in the normal direction, but access the array from the back, like so:

 

for (int i=0; i<A.length; i++)

print A[A.length - i - 1]

Answer 2

I'll give you two examples.  Let "A" be the array with which you're working

 

1. You can use a FOR loop:

 

For i = Length(A), i >= 1, i = i-1,

    Print(A[i])

 

This means increment i negatively, starting with a value equal to the length of A

 

2. Some languages allow you to specify the array components in a more concise form:

 

A[-1;;1;;-1]

 

This means list the elements of A from the -1st element (conventionally, this means the last), to the 1st element, in steps of -1

 

Of course, the proper syntax depends upon the language you are using.  Hope this helps

 

Paul