Backus-Naur-Form Grammar of C language variable declaration?

Variable is of any Data Type and Data Type can be defined as a type of value that a Variable will hold.............means which type of value you want to store, eg: fractional value (3.5454), whole...

try this, i dont know whether its what your looking for but try it.. http://www.intap.net/~drw/cpp/cpp03_01.htm

int x; float x; char x; double x; long x; long long x; short x; unsigned int x; unsigned float x; unsigned double x; signed char x; unsigned long x; unsigned long long x; int *x; float...

you have to give a statement in the following syntaxdatatype variable;

An external variable is a variable defined outside any function block. They are permanent, thus retain their value regardless of the functions.