invert()

ring_elem Z_mod::invert ( const ring_elem f ) const

virtual

Implements Ring.

Definition at line 278 of file ZZp.cpp.

{
  int a = f.get_int();
  if (a == _ZERO) throw exc::division_by_zero_error();
  if (a == 0) return 0;  // this is the case f == ONE
  return ring_elem(P - 1 - a);
}

References _ZERO, ring_elem::get_int(), and P.