Task: songer_usc1

What follows is an opinion from a United States Court of Appeals.
Your task is to identify the most frequently cited title of the U.S. Code in the headnotes to this case. Answer "0" if no U.S. Code titles are cited. If one or more provisions are cited, code the number of the most frequently cited title.

PER CURIAM.
In case No. 7164, judgment affirmed February 5, 1963, without written opinion, for the reason stated in the order of the United States District Court. In case No. 7180, appeal dismissed February 5, 1963, without written opinion, since the record conclusively shows that appellant is not now serving the sentence he attacks and relief under section 2255 is not available to him. Heflin v. United States, 358 U.S. 415, 79 S.Ct. 451, 3 L.Ed.2d 407; Igo v. United States, 10 Cir., 303 F.2d 317.

Question: What is the most frequently cited title of the U.S. Code in the headnotes to this case? Answer with a number.
Answer:

Answer: 0