Reversing an integer array

[chris]

I've been trying to reverse an array for the last little while and I can't seem to get it right. Has anybody done this before?

[sonneveld]

can't you just go

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#include <algorithm>

int myarray[10];
reverse(myarray, myarray+10);

gotta love the STL. Course this is assuming you're using C++ in the first place.

- Nick

[chris]

Err sorry I forgot this was "General Programming". I'm working in C.

[Tim]

How about this:

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for (i = 0; i < length / 2; i++)
    swap(a + i, a + length - 1 - i);

Or if you want to create a reversed copy:

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for (i = 0; i < length; i++)
    b[i] = a[i + length - 1];

[chris]

This is what I ended up with. I'm pretty sure it works, i've tested it with a bunch of different sized arrays.

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   for (i = 0; i < (length / 2); i++) {
      tmp = a[i];
      a[i] = a[length - (i+1)];
      a[length - (i+1)] = tmp;
   }