9 #ifndef IO_FORMAT_INCLUDED
10 #define IO_FORMAT_INCLUDED
35 virtual int nin()
const = 0;
36 virtual int nex()
const = 0;
38 virtual void file_to_field(
int& s,
int& t,
const int i,
const int j)
const = 0;
45 virtual int nin()
const {
return 0; }
46 virtual int nex()
const {
return 0; }
48 virtual void file_to_field(
int& s,
int& t,
const int i,
const int j)
const