List of contests in the archive:

Click on a link in the list to jump to the materials from that contest.

• Online Round 2025
• Qualification Round 2025

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Contest: online2025

Writing credits

Problems for this round were created, prepared and tested by Mišo 'misof' Forišek, Samko 'Hodobox' Gurský, Truc Lam Bui ('Buj'), MišQo Farnbauer, and Jakub 'Xellos' Šafin.

Final scoreboard:

• Scoreboard

Problem H: Heap

• Problem statement
• Solution writeup
• H1.in: Input file.
• H1.out: Output file (unique).
• H_solution.py: Reference solution in Python

Problem D: Decode the digits

• Problem statement
• Solution writeup
• D1.in: First input file.
• D1.out: First output file (unique).
• D2.in: Second input file.
• D2.out: Second output file (unique).
• D3.in: Third input file.
• D3.out: Third output file (unique).
• D4.in: Fourth input file.
• D4.out: Fourth output file (unique).
• D_solution.cpp: Reference solution in C++

Problem P: Politics

• Problem statement
• Solution writeup
• P1.in: First input file.
• P1.out: First output file (unique up to rounding).
• P2.in: Second input file.
• P2.out: Second output file (unique up to rounding).
• P3.in: Third input file.
• P3.out: Third output file (unique up to rounding).
• P4.in: Fourth input file.
• P4.out: Fourth output file (unique up to rounding).
• P_solution.cpp: Solution in C++ (with gmp_floats for extra precision).

Problem S: Slow BFS

• Problem statement
• Solution writeup
• S1.out: One possible tree that scores 100 points.
• S_checker.cpp: Checker in C++

Problem W: Walk between spots

• Problem statement
• Solution writeup
• W1.in: First input file.
• W1.out: First output file (unique).
• W2.in: Second input file.
• W2.out: Second output file (unique).
• W3.in: Third input file.
• W3.out: Third output file (unique).
• W4.in: Fourth input file.
• W4.out: Fourth output file (unique).
• W_solution.cpp: Reference solution in C++

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Contest: qual2025

Writing credits

Problems for this round were created, prepared and tested by Mišo 'misof' Forišek, Samko 'Hodobox' Gurský, Truc Lam Bui ('Buj'), Mišo 'Žaba' Anderle, and Paulínka 'paulinia' Smolárová.

Final scoreboard:

• Scoreboard

Problem N: Number pairs

• Problem statement
• Solution writeup
• N1.in: Easy input file.
• N1.out: Easy output file (one possible).
• N2.in: Medium input file.
• N2.out: Medium output file (one possible).
• N3.in: Hard input file.
• N3.out: Hard output file (one possible).
• N-sol.py: Full solution in Python
• N-checker.py: Checker in Python

Problem T: Tiling cheaply

• Problem statement
• Solution writeup
• T1.in: Easy input file.
• T1.out: Easy output file (one possible).
• T2.in: Medium input file.
• T2.out: Medium output file (one possible).
• T3.in: Hard input file.
• T3.out: Hard output file (one possible).
• T-sol.cpp: Full solution in C++
• T-checker.cpp: Checker in C++ (needs testlib.h)

Problem R: Rooks

• Problem statement
• Solution writeup
• R1.in: Easy input file.
• R1.out: Easy output file (unique).
• R2.in: Medium input file.
• R2.out: Medium output file (unique).
• R3.in: Hard input file.
• R3.out: Hard output file (unique).
• R-sol.cpp: Full solution in C++
• R-sol-slow.py: Easy subtask solution in Python

Problem B: Binary with a twist

• Problem statement
• Solution writeup
• B1.in: Easy input file.
• B1.out: Easy output file (unique).
• B2.in: Medium input file.
• B2.out: Medium output file (unique).
• B3.in: Hard input file.
• B3.out: Hard output file (unique).
• B-sol1.cpp: Reference solution in C++
• B-sol2.py: Slower but sufficient solution in Python

Problem K: Katamari

• Problem statement
• Solution writeup
• K1.in: Input file.
• K1.tsp: TSP file with the t_opt times for the checker.
• K1.out: Output file (best paths found).
• K-checker.py: Checker in Python.

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