Codeforces Round 503 (by SIS, Div. 1)

5 problems from Codeforces Round 503 (by SIS, Div. 1) (contest 1019), difficulty 1700-3200. 3/5 solutions verified against sample I/O.

5 items

Codeforces Round 503 (by SIS, Div. 1)

Div. 1 | 5 problems | 3/5 verified | Difficulty 1700-3200 | 12m 46s

#	Problem	Rating	Tags	Accepted	Time	✓
A	Elections	1700	brute-force, greedy	4,852	2m 7s	✓
B	The hat	2000	binary-search, interactive	2,112	2m 40s
C	Sergey's problem	3000	constructive-algorithms, graphs	1,454	2m 39s
D	Large Triangle	2700	binary-search, geometry, sortings	742	2m 44s	✓
E	Raining season	3200	data-structures, divide-and-conquer, trees	407	2m 36s	✓

Practice › Codeforces Solutions › Codeforces Round 503 (by SIS, Div. 1) ›

CF 1019E - Raining season

We are given a tree where each edge represents a bidirectional road between two houses. Every road has two parameters: a base traversal time and a rate at which it worsens each day. On day $t$, the cost of an edge becomes a linear function $bi + ai cdot t$.

Practice › Codeforces Solutions › Codeforces Round 503 (by SIS, Div. 1) ›

CF 1019D - Large Triangle

We are given a set of points on a plane, each point representing a city. The task is to select three distinct cities such that the triangle formed by them has a prescribed area $S$. If no such triple exists, we must report failure.

Practice › Codeforces Solutions › Codeforces Round 503 (by SIS, Div. 1) ›

CF 1019B - The hat

We are given a circle of $n$ students, where $n$ is even. Each student holds an unknown integer, and the only structural guarantee about these values is local: any two neighbors on the circle differ by exactly one in value.

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CF 1019C - Sergey's problem

We are given a directed graph with up to one million vertices and one million edges. The task is to choose a subset of vertices $Q$ with two properties that interact in a non-trivial way.

Practice › Codeforces Solutions › Codeforces Round 503 (by SIS, Div. 1) ›

CF 1019A - Elections

The election has a fixed set of voters, each initially committed to one of several parties. The United Party is party 1, and its goal is not just to get a lot of votes, but to strictly outperform every other party in final vote count.