How do we get the number of elements in an array without using sizeof

Question

How do we get the number of elements in an arraywithout using sizeof. In any case sizeof does not get me the correct number of elemnts so I want to implement my self without using sizeof.

I tried to run using sizeof and it doesn't print the correct number of elements in an array.

int n = sizeof(arr) / sizeof(arr[0]);
for (int i = 0; i < n; i++){
printf("%s\n", arr[i]);
}   
// to check if the noof elts in the arr is correct 
printf("%d\n", n);

Answer 1

When you use an array as an argument in a function call, it is automatically converted to a pointer to its first element. The C standard does not provide any means for finding the size of an array given only a pointer to its first element.

For a function to know the size of an array that is passed to it in this way, you must pass the size as a separate argument or must provide the function some other way of knowing the size, such as including a sentinel value to mark the end. (For example, the null character that marks the end of a string is a sentinel.)