during make file the warning "try.c:5: warning: return type of 'main' is not `int'".always shows. and how to solve the warning "try.c:30: warning: `return' with a value, in function returning void"
For the first warning i think you just have to declare the main function as int main(), not void main(). The second warning says you are returning some value from a function, which is declared not to return anything. I guess this is because of the main() function, so the solution above should fix both warnings.