Codeforces Round 258 (Div. 2)

5 problems from Codeforces Round 258 (Div. 2) (contest 451), difficulty 900-2300. 5/5 solutions verified against sample I/O.

5 items

Codeforces Round 258 (Div. 2)

Div. 2 | 5 problems | 5/5 verified | Difficulty 900-2300 | 8m 33s

#	Problem	Rating	Tags	Accepted	Time	✓
A	Game With Sticks	900	implementation	75,667	1m 19s	✓
B	Sort the Array	1300	implementation, sortings	52,822	1m 39s	✓
C	Predict Outcome of the Game	1700	brute-force, implementation, math	3,579	1m 55s	✓
D	Count Good Substrings	2000	math	5,061	2m 3s	✓
E	Devu and Flowers	2300	bitmasks, combinatorics, number-theory	4,540	1m 37s	✓

Practice › Codeforces Solutions › Codeforces Round 258 (Div. 2) ›

CF 451A - Game With Sticks

The game is played on a grid formed by n horizontal sticks and m vertical sticks. Every horizontal stick intersects every vertical stick, creating n m intersection points. On a turn, a player chooses one remaining intersection point.

Practice › Codeforces Solutions › Codeforces Round 258 (Div. 2) ›

CF 451B - Sort the Array

We are given an array of distinct integers. The task is to determine whether the entire array can become sorted in increasing order after reversing exactly one contiguous segment. If it is possible, we must print "yes" and one valid segment [l, r] whose reversal sorts the array.

Practice › Codeforces Solutions › Codeforces Round 258 (Div. 2) ›

CF 451C - Predict Outcome of the Game

We have a football tournament involving three teams. Every game produces exactly one winner, so each played game contributes exactly one win to one of the teams. After k games have already been played, we do not know the exact number of wins of the three teams.

Practice › Codeforces Solutions › Codeforces Round 258 (Div. 2) ›

CF 451D - Count Good Substrings

We are given a binary string consisting only of 'a' and 'b'. For every substring, we repeatedly merge consecutive equal characters into a single character.

Practice › Codeforces Solutions › Codeforces Round 258 (Div. 2) ›

CF 451E - Devu and Flowers

We have n flower boxes. From box i, we may take any number of flowers between 0 and f[i], inclusive. The colors are distinct, so a selection is completely described by how many flowers we take from each box.