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Syntax & Styling

• Instead of #defineing size to be 10, you should declare a static const.

   static const size = 10;
  

  This answer explains nicely as to why. Good job on having this declared though, it's better than having magic numbers in your code.

• You should never declare main() to return void. There is no good reason to not declare it as int main(). See this answer for more explanation.

• You should declare your main with void parameters, as such:

   int main(void) 
  

• Your main() is doing too much within it. You should abstract your code into different functions and then call it from within main().

• Put the variable declarations to separate lines and initialize them to some value. From Code Complete, 2d Edition, p. 759:

With statements on their own lines, the code reads from top to bottom, instead of top to bottom and left to right. When you’re looking for a specific line of code, your eye should be able to follow the left margin of the code. It shouldn’t have to dip into each and every line just because a single line might contain two statements.

• You should declare your for loops as such:

   for(int i=0; i < size; ++i)
  

  Note that this was introduced in the C99 standard. There is no reason you should not be using this standard in your code.

Algorithm

• Why do you limit yourself to finding palindromes within an int array? It's more typical to find palindromes within a string.

• Right now the time complexity for your algorithm is \$ O(n^3) \$, which is expensive. Let's use Manacher's algorithm which can do it in \$ O(n) \$. Here is a C implementation of the algorithm, but recognize that this has some bad practices within the code and should only be looked at to get an idea for implementing the algorithm yourself.