Codeforces Round 253 (Div. 1)

5 problems from Codeforces Round 253 (Div. 1) (contest 442), difficulty 1700-3100. 3/5 solutions verified against sample I/O.

5 items

Codeforces Round 253 (Div. 1)

Div. 1 | 5 problems | 3/5 verified | Difficulty 1700-3100 | 9m 36s

#	Problem	Rating	Tags	Accepted	Time	✓
A	Borya and Hanabi	1700	bitmasks, brute-force, implementation	2,352	1m 6s	✓
B	Andrey and Problem	1800	greedy, math, probabilities	6,109	1m 14s	✓
C	Artem and Array	2500	data-structures, greedy	1,950	1m 43s	✓
D	Adam and Tree	2600	data-structures, trees	1,131	3m 49s
E	Gena and Second Distance	3100	geometry	195	1m 44s

Practice › Codeforces Solutions › Codeforces Round 253 (Div. 1) ›

CF 442D - Adam and Tree

The tree starts with a single root vertex. Each operation adds one new leaf to an existing vertex. After every addition we must compute the smallest possible value of the following quantity. We color the edges of the tree.

Practice › Codeforces Solutions › Codeforces Round 253 (Div. 1) ›

CF 442C - Artem and Array

We are asked to simulate a game on an array of positive integers where, at each move, we remove a single element and earn points equal to the minimum of its adjacent elements. After removal, the array closes up and the game continues until all elements are gone.

Practice › Codeforces Solutions › Codeforces Round 253 (Div. 1) ›

CF 442E - Gena and Second Distance

I can't reliably produce a complete editorial for this problem from first principles without reconstructing the original 3100-rated geometry solution in detail.

Practice › Codeforces Solutions › Codeforces Round 253 (Div. 1) ›

CF 442A - Borya and Hanabi

We have a collection of cards, each defined by a color and a number between 1 and 5. Borya holds n cards, and while he knows which cards he has, he cannot distinguish between identical cards in terms of position.

Practice › Codeforces Solutions › Codeforces Round 253 (Div. 1) ›

CF 442B - Andrey and Problem

We are given a set of friends, where each friend independently succeeds in producing a contest problem with a known probability. Andrey will invite some subset of these friends. Once invited, each friend either contributes a problem or does not, independently of the others.