Codeforces Round 181 (Div. 2)

5 problems from Codeforces Round 181 (Div. 2) (contest 300), difficulty 1100-2300. 3/5 solutions verified against sample I/O.

5 items

Codeforces Round 181 (Div. 2)

Div. 2 | 5 problems | 3/5 verified | Difficulty 1100-2300 | 8m 21s

#	Problem	Rating	Tags	Accepted	Time	✓
A	Array	1100	brute-force, constructive-algorithms, implementation	27,175	1m 26s	✓
B	Coach	1500	brute-force, dfs-and-similar, graphs	7,148	2m 11s
C	Beautiful Numbers	1800	brute-force, combinatorics	11,742	1m 15s	✓
D	Painting Square	2300	dp, fft	855	1m 48s
E	Empire Strikes Back	2300	binary-search, math, number-theory	1,103	1m 41s	✓

Practice › Codeforces Solutions › Codeforces Round 181 (Div. 2) ›

CF 300B - Coach

We are asked to divide n students into teams of exactly three. Some students explicitly request to be on the same team with certain other students. These requests are mutual, so if student 2 wants to team with student 5, then student 5 also wants student 2.

Practice › Codeforces Solutions › Codeforces Round 181 (Div. 2) ›

CF 300C - Beautiful Numbers

We are given two fixed digits, and we are allowed to build length-n numbers using only those two digits. Any such number is considered “valid” in the first sense, because every position is constrained to a two-element alphabet instead of the full decimal set.

Practice › Codeforces Solutions › Codeforces Round 181 (Div. 2) ›

CF 300E - Empire Strikes Back

We are asked to determine the minimum positive integer $n$ such that the factorial $n!$ divided by a set of numbers $[a1, a2, dots, ak]$ produces an integer. In other words, the Empire has a strike strength $n!$, and each Republican strike is represented by $ai$.

Practice › Codeforces Solutions › Codeforces Round 181 (Div. 2) ›

CF 300D - Painting Square

We are given a square table of size n × n, initially all white, with a black border around the edges. Vasily the bear can perform exactly k painting moves.

Practice › Codeforces Solutions › Codeforces Round 181 (Div. 2) ›

CF 300A - Array

We are given an array of distinct integers and asked to split it into three non-empty sets. The first set must have a product less than zero, the second set a product greater than zero, and the third set a product equal to zero.