Halim, S., & Halim, F. (2020). Competitive programming 4: The lower bound of programming contests in the 2020s. Ingram content group.
Chicago-viite (17. p.)Halim, Steven, ja Felix Halim. Competitive Programming 4: The Lower Bound of Programming Contests in the 2020s. United States, UK: Ingram content group, 2020.
MLA-viite (8. p.)Halim, Steven, ja Felix Halim. Competitive Programming 4: The Lower Bound of Programming Contests in the 2020s. Ingram content group, 2020.
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