GENERAL PART
Aim of the Criminal Code
Chapter I
Scope of the Criminal Code
Effect of Foreign Verdicts
Section 6
(5) If an act of a person falling under the jurisdiction of Hungarian criminal law has already been adjudicated by a foreign court, with the exception set forth in Subsection (1), the Attorney General shall decide on the institution of criminal proceedings. In such case, the time of sentence served in a foreign country or the time of detention shall be deducted from the sentence imposed by the Hungarian court.
Ne bis in idem
Ne bis in idem - State's own court
Reduction of national sentence following pre-trial detention - national proceedings
EDIT.