How to check array value at specific index

[imnotprogrammer]

hello everyone, how can I check that value at specific index of an array is empty or not. for example

void storeAt( int index,int val)
{
   arr[index] = val //arr[] has been declared in class
}

I can put value only if arr[index] is empty, if already occupied I cannot add value. how can I check arr[index] is empty?

[vlad from moscow]

First of all you should define what means an element is empty.

[imnotprogrammer]

element obviously cannot be empty. im talking about the array's index

[vlad from moscow]

Read one more what I wrote if you can not understand what I said.

[vlad from moscow]

If you meant to check whether an element is equal to some value when you can write

bool storeAt( int index,int val)
{
   return arr[index] == val;
}