East China University of Science and Technology Programming Contest 2025
15 problems from East China University of Science and Technology Programming Contest 2025 (contest 106136), difficulty -. 15/15 solutions verified against sample I/O.
East China University of Science and Technology Programming Contest 2025
Special | 15 problems | 15/15 verified | Difficulty - | 15m 31s
| # | Problem | Rating | Tags | Accepted | Time | ✓ |
|---|---|---|---|---|---|---|
| A | Golden Alleyway | 41s | ✓ | |||
| B | Seeing is believing | 49s | ✓ | |||
| C | Time Trouble | 50s | ✓ | |||
| D | Mosaic Garden | 55s | ✓ | |||
| E | Fortress Fall | 1m 11s | ✓ | |||
| F | The Tower(XVI) | 52s | ✓ | |||
| G | Midnight Monsoon | 1m 16s | ✓ | |||
| H | Square the Circle | 59s | ✓ | |||
| I | Chromatic Complex | 1m 8s | ✓ | |||
| J | Attack from clone | 1m 28s | ✓ | |||
| K | Clockwork | 1m 9s | ✓ | |||
| L | Forest Path | 1m 13s | ✓ | |||
| M | FLOATING POINT | 50s | ✓ | |||
| N | In Filtration | 55s | ✓ | |||
| O | Nelumbo | 1m 15s | ✓ |
CF 106136L - Forest Path
We start with a tree on n vertices. Then one extra edge is added between two previously non-adjacent vertices, turning the structure into a single cycle graph with exactly one cycle. We are not directly told which edge was added.
CF 106136G - Midnight Monsoon
We are given a dynamic multiset of numbers representing pufferfish sizes. After each update, we are allowed to reorder all values arbitrarily into a permutation.
CF 106136N - In Filtration
We are working on an infinite grid where a white king starts at a given coordinate and must eventually capture all black rooks. The king moves like a standard chess king, meaning it can step to any of the eight neighboring cells in one move.
CF 106136H - Square the Circle
We are interacting with a hidden geometric shape centered at the origin. In each test case, the hidden object is either a circle or a square, both centered at $(0,0)$, and we can only probe it by asking whether specific integer lattice points lie inside it.
CF 106136A - Golden Alleyway
We are given a small ICPC team and a record of how many medals the team wins in a contest. Each gold, silver, and bronze medal corresponds to a fixed prize pool: gold is worth 7500 yuan per team, silver is 3000 yuan per team, and bronze is 1500 yuan per team.
CF 106136K - Clockwork
We are given an array of length $n$, initially all zeros, and we are allowed to overwrite parts of it using very structured “clock-like” operations. Each operation picks a position $k$ and then writes a distance pattern either to the left side or to the right side of $k$.
CF 106136D - Mosaic Garden
We are working with a fixed string, ECUST, and the task is to generate every possible string that can be formed by independently choosing the case of each character while keeping the underlying letters unchanged.
CF 106136O - Nelumbo
We are working with a tree where each node carries an integer weight. For every pair of distinct nodes, we look at the unique path between them and collect all node weights along that path.
CF 106136M - FLOATING POINT
We are asked to construct a strictly increasing sequence of length $n$, where every element is a non-negative integer below $2^{30}$.
CF 106136J - Attack from clone
We are given an initial multiset of integers that already has a very rigid structure: it is an arithmetic progression of length $n$, starting at $a1$ with common difference $d$. So the starting set is completely determined and sorted automatically.
CF 106136I - Chromatic Complex
We are given a large grid where each cell is either land, water, or lava. Lava is forbidden, while land and water are traversable.
CF 106136E - Fortress Fall
We are given a list of ingredient freshness values and two fixed recipe coefficients. Each day, Maddy must pick exactly two unused ingredients and assign them to the two recipes in any order.
CF 106136F - The Tower(XVI)
We start with a decimal number written on a stone. Each time we press a mechanism, we transform the number by replacing every digit independently with the square of that digit, written in decimal, and then concatenating these squared values in the same order.
CF 106136C - Time Trouble
We are given two small integers for each test case, and we must decide whether we can interpret them as the two fields of a valid 24-hour clock time in the format HH:MM.
CF 106136B - Seeing is believing
We are given a small integer range defined by a starting point l. The hidden number a is guaranteed to lie somewhere in the interval from l up to l + 5, so at most six consecutive integers are possible candidates.