Next time you post code use code tags please.
I´m not sure you can do like this, I assume that theese functions
do the same thing, use one function only. Also should it return a datatype which is the same as WIN, CONTINUE and DRAW
You should always assign a value to a varible before you use it. Varible a is unneccesary and r contain garbage-value which mean that you don´t compare the array correctly.
Should be if (board[i] == ´´)
for(c=0; c<9; ++c)
if (board[r] == ' ')
return CONTINUE; // Game is not finished
Make also sure that the function returns the right datatype.
Hope that helps!