2D array in C

If I have something like

char a[50][50];

Is something like this OK to do:

memset(a,0,2500);

In other words, does C make it into one array or is it actually an array of pointers?

>>9
memset(a, 0, 2500); is fine. you can cast a to (void*) if your compiler is a nazi but it shouldn't give errors.