The 2025 Sichuan Provincial Collegiate Programming Contest

12 problems from The 2025 Sichuan Provincial Collegiate Programming Contest (contest 105949), difficulty -. 12/12 solutions verified against sample I/O.

12 items

The 2025 Sichuan Provincial Collegiate Programming Contest

Special | 12 problems | 12/12 verified | Difficulty - | 13m 16s

#	Problem	Time	✓
A	Minimum Product	1m 15s	✓
B	Ternary	1m 8s	✓
C	Optimal Time	1m 23s	✓
D	Tripartite Graph	1m 9s	✓
E	Competition Graph	1m 21s	✓
F	Inversion Pairs	1m 2s	✓
G	Diophantine Equation	1m 5s	✓
H	Hututu	54s	✓
I	Essentially Different Suffixes	59s	✓
J	Sichuan Provincial Contest	1m 8s	✓
K	Point Divide and Conquer	1m	✓
L	abc	52s	✓

Practice › Codeforces Solutions › The 2025 Sichuan Provincial Collegiate Programming Contest ›

CF 105949L - abc

We are given a string composed only of the characters a, b, and c. The task is to look at every contiguous substring and assign it a score based on how uneven the character distribution is inside that substring.

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CF 105949J - Sichuan Provincial Contest

We are given a tree, and every node carries a single uppercase letter. A query asks us to count how many simple paths in this tree contain exactly five nodes, and if we read the letters along the path in order, they must form the fixed pattern “S C C P C”.

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CF 105949K - Point Divide and Conquer

We are given a tree with labeled nodes and a fixed permutation that determines an order of processing. The construction builds a rooted tree by repeatedly selecting, from the currently remaining nodes, the one that appears earliest in the permutation among those still present.

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CF 105949I - Essentially Different Suffixes

We are given several strings, and we conceptually take every suffix from every string. A suffix is any substring that starts at some position and continues to the end. For example, in a string like “abc”, its suffixes are “abc”, “bc”, and “c”.

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CF 105949E - Competition Graph

We are given a complete directed graph on $n$ labeled vertices where every pair of vertices has exactly one directed edge between them, forming a tournament. Among all such tournaments, we need to count how many contain at least one directed simple cycle of length exactly $k$.

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CF 105949G - Diophantine Equation

We are given a sequence of numbers that we can think of as defining a polynomial-like transformation over a modular field.

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CF 105949F - Inversion Pairs

We are given a binary sequence where every position is supposed to end up as either 0 or 1, but some positions are currently unknown. The unknown positions can be filled freely with 0 or 1.

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CF 105949A - Minimum Product

We are given a directed graph where every edge carries two small positive weights. A path from node 1 to node N accumulates these weights separately: one sum is formed by adding all first components along the path, and another sum is formed by adding all second components.

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CF 105949D - Tripartite Graph

We are given a permutation $q$ of length $n$. We need to count how many permutations $p$ of the same length satisfy two conditions. First, $p$ must be lexicographically larger than $q$.

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CF 105949B - Ternary

We are given a hidden “encryption system” that works digit by digit on base-3 numbers of length $n$. At each position $i$, there is a fixed permutation $fi$ of the digits ${0,1,2}$.

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CF 105949H - Hututu

We are given a point on an infinite integer grid and a target point. In one move, the token can change its position by stepping in a “knight-like but diagonal-biased” pattern: both coordinates change together, and the allowed absolute step pairs are (1,1), (2,2), (1,2), or…

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CF 105949C - Optimal Time

We are looking at a system that evolves on integers from 0 to N. From a current state x, each second gives you a single decision before anything else happens. If you choose the passive option, the state simply moves deterministically from x to x − 1 after one second.