2021 Jiangsu Collegiate Programming Contest

12 problems from 2021 Jiangsu Collegiate Programming Contest (contest 103495), difficulty -. 12/12 solutions verified against sample I/O.

12 items

2021 Jiangsu Collegiate Programming Contest

Special | 12 problems | 12/12 verified | Difficulty - | 10m 19s

# Problem Rating Tags Accepted Time ✓
A Spring Couplets 43s ✓
B Among Us 49s ✓
C Magical Rearrangement 46s ✓
D Pattern Lock 46s ✓
E Stone Ocean 49s ✓
F Jumping Monkey II 48s ✓
G Five Phases 58s ✓
H Reverse the String 53s ✓
I Fake Walsh Transform 46s ✓
J Anti-merge 52s ✓
K Longest Continuous 1 1m 10s ✓
L Tree Game 59s ✓
Practice › Codeforces Solutions › 2021 Jiangsu Collegiate Programming Contest ›

CF 103495K - Longest Continuous 1

We are building a very large binary string by repeatedly appending binary representations of integers. The construction starts from a single character string “0”.
codeforces competitive-programming Jul 3, 2026
Practice › Codeforces Solutions › 2021 Jiangsu Collegiate Programming Contest ›

CF 103495L - Tree Game

We are given a rooted tree with nodes labeled from 1 to n, where node 1 is the root. Each node initially holds a value, and these values form a partial permutation: some nodes already contain distinct numbers, while others are empty and marked as zero.
codeforces competitive-programming Jul 3, 2026
Practice › Codeforces Solutions › 2021 Jiangsu Collegiate Programming Contest ›

CF 103495J - Anti-merge

We are given an $n times m$ grid where each cell contains an integer value. There is a merging system that operates in two passes. First, within every column, vertically adjacent cells that share the same visible value get merged into a single taller block.
codeforces competitive-programming Jul 3, 2026
Practice › Codeforces Solutions › 2021 Jiangsu Collegiate Programming Contest ›

CF 103495H - Reverse the String

We are given a string consisting only of lowercase English letters. In one move, we are allowed to pick a contiguous segment of the string and reverse it, or we may choose to leave the string unchanged.
codeforces competitive-programming Jul 3, 2026
Practice › Codeforces Solutions › 2021 Jiangsu Collegiate Programming Contest ›

CF 103495G - Five Phases

We are given a system with five quantities corresponding to the five classical phases: Wood, Fire, Earth, Metal, and Water. Initially all five quantities are zero.
codeforces competitive-programming Jul 3, 2026
Practice › Codeforces Solutions › 2021 Jiangsu Collegiate Programming Contest ›

CF 103495I - Fake Walsh Transform

We are given a full set of integers from 0 up to $2^m - 1$, meaning all binary masks of length $m$. From this universe we want to pick a subset of distinct numbers. The only requirement on the chosen subset is that the XOR of all chosen values must equal a fixed target value $n$.
codeforces competitive-programming Jul 3, 2026
Practice › Codeforces Solutions › 2021 Jiangsu Collegiate Programming Contest ›

CF 103495F - Jumping Monkey II

We are given a tree where each node carries a numeric value. From any starting node, a monkey is allowed to walk along edges without revisiting nodes, so every valid walk corresponds to a simple path in the tree.
codeforces competitive-programming Jul 3, 2026
Practice › Codeforces Solutions › 2021 Jiangsu Collegiate Programming Contest ›

CF 103495E - Stone Ocean

We are given several strings, and from each string we independently pick one character uniformly at random. If we call the chosen characters $T1, T2, dots, Tn$, then each $Ti$ is drawn from $Si$ with equal probability over its positions, and the resulting string $T$ has length…
codeforces competitive-programming Jul 3, 2026
Practice › Codeforces Solutions › 2021 Jiangsu Collegiate Programming Contest ›

CF 103495D - Pattern Lock

We are given an $n times m$ grid of equally spaced points, where each point $(x, y)$ is a selectable node. The task is to output an ordering of all $n cdot m$ points such that we visit every point exactly once and move between consecutive points with straight segments.
codeforces competitive-programming Jul 3, 2026
Practice › Codeforces Solutions › 2021 Jiangsu Collegiate Programming Contest ›

CF 103495B - Among Us

We are given a map of rooms connected by weighted undirected paths. Two impostors start at fixed rooms and can only move along these weighted secret paths.
codeforces competitive-programming Jul 3, 2026
Practice › Codeforces Solutions › 2021 Jiangsu Collegiate Programming Contest ›

CF 103495C - Magical Rearrangement

We are given counts of digits from 0 to 9. Think of it as having a multiset of digits, where digit d appears exactly a[d] times.
codeforces competitive-programming Jul 3, 2026
Practice › Codeforces Solutions › 2021 Jiangsu Collegiate Programming Contest ›

CF 103495A - Spring Couplets

We are given several independent test cases, where each test case consists of two equal-length lines of “characters”. Each character is represented as a short string ending with a digit that encodes its tone.
codeforces competitive-programming Jul 3, 2026