The 2025 ICPC Asia EC Regionals Online Contest (II)

12 problems from The 2025 ICPC Asia EC Regionals Online Contest (II) (contest 106072), difficulty -. 12/12 solutions verified against sample I/O.

12 items

The 2025 ICPC Asia EC Regionals Online Contest (II)

ICPC/IOI | 12 problems | 12/12 verified | Difficulty - | 12m 6s

#	Problem	Time	✓
A	Angry Birds	59s	✓
B	Rectangular Wooden Block	58s	✓
C	Jiaxun!	53s	✓
D	Arcane Behemoths	48s	✓
E	Zero	1m 5s	✓
F	Square Permutation I	56s	✓
G	Square Permutation II	53s	✓
H	Tree Shuffling	1m 8s	✓
I	DAG Query	1m 15s	✓
J	Reconstruct the tree	1m 7s	✓
K	The Only Heart	1m 16s	✓
L	Xor Mirror	48s	✓

Practice › Codeforces Solutions › The 2025 ICPC Asia EC Regionals Online Contest (II) ›

CF 106072I - DAG Query

We are given the full structure of a directed acyclic graph, but the weights of the edges are unknown. The only way to learn anything about the weights is through an interactive oracle: we choose a pair of vertices $s, t$ and a scalar $c$, and the oracle returns the sum over…

Practice › Codeforces Solutions › The 2025 ICPC Asia EC Regionals Online Contest (II) ›

CF 106072A - Angry Birds

We are given a closed polyline drawn in the plane $z = 0$. In simpler terms, there are $n$ points in the XY-plane, and they are connected in a cycle: each point connects to the next, and the last connects back to the first.

Practice › Codeforces Solutions › The 2025 ICPC Asia EC Regionals Online Contest (II) ›

CF 106072L - Xor Mirror

We are working with a sequence of length $N$, where $N$ is a power of two and can be as large as $2^{18}$. The array supports two operations that both act on a segment $[l, r)$.

Practice › Codeforces Solutions › The 2025 ICPC Asia EC Regionals Online Contest (II) ›

CF 106072E - Zero

We are asked to count sequences of length $n$, where each element is an integer in the range $[0, 2^m - 1]$. Two conditions must hold simultaneously. First, no two adjacent elements are allowed to be equal.

Practice › Codeforces Solutions › The 2025 ICPC Asia EC Regionals Online Contest (II) ›

CF 106072G - Square Permutation II

We are given two permutations of the same length, call them $p$ and $q$. Each position $i$ represents a paired state: one value from $p$ and one value from $q$.

Practice › Codeforces Solutions › The 2025 ICPC Asia EC Regionals Online Contest (II) ›

CF 106072K - The Only Heart

We are given a tree and we consider all ways to delete vertices so that the remaining vertices still form a connected subgraph. In a tree, any connected induced vertex set is again a tree, so every valid choice corresponds to picking a connected subtree.

Practice › Codeforces Solutions › The 2025 ICPC Asia EC Regionals Online Contest (II) ›

CF 106072D - Arcane Behemoths

We are given an array of integers, where each value represents the initial attack power of a creature. From this array we can pick any non-empty subsequence, meaning we may choose any subset of indices while keeping their original order.

Practice › Codeforces Solutions › The 2025 ICPC Asia EC Regionals Online Contest (II) ›

CF 106072H - Tree Shuffling

We are given a tree where every vertex initially carries a distinct label equal to its index. The only allowed action is a single global operation that changes some of these labels. In that operation, we first pick a simple path in the tree.

Practice › Codeforces Solutions › The 2025 ICPC Asia EC Regionals Online Contest (II) ›

CF 106072C - Jiaxun!

We are given a pool of programming problems, each problem already labeled by exactly which of three students can solve it. Every problem falls into one of seven categories depending on its solvability set among students 1, 2, and 3.

Practice › Codeforces Solutions › The 2025 ICPC Asia EC Regionals Online Contest (II) ›

CF 106072J - Reconstruct the tree

We are given a tree with nodes labeled from 1 to N, but the tree itself is lost. What remains is a list of pairs of nodes that were remembered as being at maximum possible distance in that tree, meaning each listed pair has distance equal to the tree’s diameter.

Practice › Codeforces Solutions › The 2025 ICPC Asia EC Regionals Online Contest (II) ›

CF 106072F - Square Permutation I

We are given two permutations of the same length, and each position represents a paired choice between two values, one coming from the first permutation and one from the second. At every index we are allowed to “activate” some transformation on the values at that index.

Practice › Codeforces Solutions › The 2025 ICPC Asia EC Regionals Online Contest (II) ›

CF 106072B - Rectangular Wooden Block

We are given a 3D wooden block composed of unit cubes arranged in a grid of size $L times W times H$. Each cube $(i,j,k)$ can be reinforced at some cost, and if we choose to reinforce it, we pay $V(i,j,k)$.