How can I get the size of a multidimensional int/char array?

Code:
int array[80][80]= {{1,2,3},{4,5,6,7},{8,9,10,11,12}};
If I have that as example.

How can I get it to return the actual size of the array, the inner arrays (not the outer)?

Using the normal sizeOf will return just the entire size of the array as I specified [80][80] but not the actual size of the arrays.
Code:
int myLength = sizeof(array)/sizeof(int);