c++ - template in cpp -

i hav following piece of code in module.

controller name of class. allocate_route member function of it.

while defining member function given as

template<ui num_ip> void controller<num_ip>::allocate_route() { } 

ui unsigned integer. num_ip not defined where. has not used num_ip anywhere inside code. tell compiler statement. not able comprehend use of templates here. wat code do?

that code implements function allocate_route defined in template class controller.

when creating template classes, have 2 way implement functions:

template <int a> class {    void x() { ... } }; 

or

template <int a> class {    void x(); };  template <int a> void a<a>::x() { }