XXVIII Interregional Programming Olympiad, Vologda SU, 2026

10 problems from XXVIII Interregional Programming Olympiad, Vologda SU, 2026 (contest 106500), difficulty -. 7/10 solutions verified against sample I/O.

10 items

XXVIII Interregional Programming Olympiad, Vologda SU, 2026

Special | 10 problems | 7/10 verified | Difficulty - | 6m 46s

#	Problem	Time	✓
A	Squares and Triangles	49s	✓
B	Pair Partitioning	45s
C	Progression	29s
D	Combination Lock	44s	✓
E	Colored Balls - 1	22s
F	Colored Balls - 2	40s	✓
G	Self-Synchronizing Code	48s	✓
H	No More Than Two in a Row	47s	✓
I	Transitive Closure	37s	✓
J	Valuable Prizes	45s	✓

Practice › Codeforces Solutions › XXVIII Interregional Programming Olympiad, Vologda SU, 2026 ›

CF 106500J - Valuable Prizes

The contest organizers have gift cards and want to give exactly seven of them to the top seven contestants. After sorting the chosen cards from the first place prize down to the seventh place prize, the values must satisfy two fairness rules.

Practice › Codeforces Solutions › XXVIII Interregional Programming Olympiad, Vologda SU, 2026 ›

CF 106500I - Transitive Closure

We are given a directed graph where vertices represent states and edges represent one-step transitions from one state to another.

Practice › Codeforces Solutions › XXVIII Interregional Programming Olympiad, Vologda SU, 2026 ›

CF 106500H - No More Than Two in a Row

The game is played on a one dimensional strip of cells. Initially every cell is empty. Players alternate choosing an empty position and placing a cross there. A move is allowed only if the resulting strip does not contain three consecutive crosses.

Practice › Codeforces Solutions › XXVIII Interregional Programming Olympiad, Vologda SU, 2026 ›

CF 106500G - Self-Synchronizing Code

We have a collection of three-dimensional attribute vectors. One move chooses a single vector, chooses any subset of its three coordinates, and adds one or subtracts one from all chosen coordinates at the same time.

Practice › Codeforces Solutions › XXVIII Interregional Programming Olympiad, Vologda SU, 2026 ›

CF 106500F - Colored Balls - 2

We are given a line of balls, each painted in one of up to ten possible colors. The only operation allowed is swapping two neighboring balls, and each swap costs one unit.

Practice › Codeforces Solutions › XXVIII Interregional Programming Olympiad, Vologda SU, 2026 ›

CF 106500D - Combination Lock

The game does not actually depend on the exact digits written on the two locks. Charlie only records whether each pair of corresponding wheels is equal or different.

Practice › Codeforces Solutions › XXVIII Interregional Programming Olympiad, Vologda SU, 2026 ›

CF 106500E - Colored Balls - 1

I can write the editorial, but the problem statement you provided is missing after the headings. I found that Codeforces Gym 106500E "Colored Balls - 1" is the problem where we have a row of balls with three colors and need the minimum swaps so that each color appears in one…

Practice › Codeforces Solutions › XXVIII Interregional Programming Olympiad, Vologda SU, 2026 ›

CF 106500A - Squares and Triangles

We are given two integers, $a$ and $b$, describing a linear arrangement of shapes placed in a row. In this row there are exactly two triangles and all remaining shapes are squares. The geometry constraint is described in a relative way.

Practice › Codeforces Solutions › XXVIII Interregional Programming Olympiad, Vologda SU, 2026 ›

CF 106500B - Pair Partitioning

I can write the full editorial, but the actual problem statement is missing from the prompt. The sections titled “Problem Statement”, “Input”, and “Output” are empty, and I cannot determine the intended algorithm from only the title “Codeforces 106500B - Pair…

Practice › Codeforces Solutions › XXVIII Interregional Programming Olympiad, Vologda SU, 2026 ›

CF 106500C - Progression

I can write the full editorial in that format, but I need the actual problem statement for Codeforces 106500C - Progression first. The statement fields in your prompt are empty, and I cannot reliably identify the problem from the ID alone.