Codeforces Round 453 (Div. 1)

5 problems from Codeforces Round 453 (Div. 1) (contest 901), difficulty 1500-3300. 3/5 solutions verified against sample I/O.

5 items

Codeforces Round 453 (Div. 1)

Div. 1 | 5 problems | 3/5 verified | Difficulty 1500-3300 | 12m 51s

# Problem Rating Tags Accepted Time ✓
A Hashing Trees 1500 constructive-algorithms, trees 5,377 2m 56s
B GCD of Polynomials 2200 constructive-algorithms, math 1,640 2m 34s ✓
C Bipartite Segments 2300 binary-search, data-structures, dfs-and-similar 1,298 2m 44s ✓
D Weighting a Tree 2700 constructive-algorithms, dfs-and-similar, graphs 630 2m 17s
E Cyclic Cipher 3300 fft, math 98 2m 20s ✓
Practice › Codeforces Solutions › Codeforces Round 453 (Div. 1) ›

CF 901E - Cyclic Cipher

We are given two integer sequences of length $n$. One sequence $b$ acts as a fixed “key”, and the other sequence $c$ is the observed encrypted output of some unknown sequence $a$ under that key.
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Practice › Codeforces Solutions › Codeforces Round 453 (Div. 1) ›

CF 901D - Weighting a Tree

We are given a connected undirected graph where every edge must eventually receive an integer weight. For each vertex, we are also given a target value, and the requirement is that if you look at all edges incident to a vertex and sum their weights, that sum must exactly match…
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Practice › Codeforces Solutions › Codeforces Round 453 (Div. 1) ›

CF 901A - Hashing Trees

We are given a rooted tree described indirectly through a “level size profile.” Instead of edges, we only know how many nodes exist at each distance from the root.
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Practice › Codeforces Solutions › Codeforces Round 453 (Div. 1) ›

CF 901C - Bipartite Segments

We are given a graph whose vertices are arranged in a fixed line from 1 to n. The edges are arbitrary, but the structure is restricted so that the graph does not contain any cycle of even length when edges are treated as simple undirected edges.
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Practice › Codeforces Solutions › Codeforces Round 453 (Div. 1) ›

CF 901B - GCD of Polynomials

We are asked to construct two integer polynomials, each of degree at most $n$, with very small coefficients (each coefficient is either -1, 0, or 1), and both leading coefficients equal to 1.
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