Codeforces Round 785 (Div. 2)

Solutions for Codeforces Round 785 (Div. 2) (contest 1673). 1/6 problems verified against sample I/O. Difficulty range: 800-2500.

6 items

Codeforces Round 785 (Div. 2)

Type: Div. 2 | Problems: 6 | Verified: 1/6 | Rating range: 800-2500 | Time: 17m 48s

Problem	Name	Rating	Tags	Solve Time	Verified
A	Subtle Substring Subtraction	800	games, greedy, strings	1m 51s	✓
B	A Perfectly Balanced String?	1100	brute-force, greedy, strings	2m 4s	✗
C	Palindrome Basis	1500	brute-force, dp, math	7m 36s	✗
D	Lost Arithmetic Progression	1900	combinatorics, math, number-theory	2m 20s	✗
E	Power or XOR?	2500	bitmasks, combinatorics, math	2m 8s	✗
F	Anti-Theft Road Planning	2400	bitmasks, constructive-algorithms, divide-and-conquer	1m 49s	✗

Practice › Codeforces Solutions › Codeforces Round 785 (Div. 2) ›

CF 1673C - Palindrome Basis

The runtime error ValueError: min() arg is empty comes from trying to compute min(arr) when arr is empty. The root cause is that the input parsing logic does not match the problem's actual input format.

Practice › Codeforces Solutions › Codeforces Round 785 (Div. 2) ›

CF 1673F - Anti-Theft Road Planning

We are asked to design a system of roads on an $n times n$ grid of buildings where each road has a positive integer length and the sum of all road lengths does not exceed 48,000.

Practice › Codeforces Solutions › Codeforces Round 785 (Div. 2) ›

CF 1673D - Lost Arithmetic Progression

We are given two arithmetic progressions, $B$ and $C$. The progression $C$ contains all numbers that are common to some unknown progression $A$ and $B$. Our goal is to count how many finite arithmetic progressions $A$ could exist that satisfy this property.

Practice › Codeforces Solutions › Codeforces Round 785 (Div. 2) ›

CF 1673E - Power or XOR?

We are given a sequence of integers $B1, B2, dots, Bn$. Each value $Bi$ represents a power of two, so we can think of the underlying numbers as $Ai = 2^{Bi}$.

Practice › Codeforces Solutions › Codeforces Round 785 (Div. 2) ›

CF 1673B - A Perfectly Balanced String?

The problem defines a very strong constraint on a string: every substring must have almost equal counts of all characters that appear in the full string.

Practice › Codeforces Solutions › Codeforces Round 785 (Div. 2) ›

CF 1673A - Subtle Substring Subtraction

We are given several independent rounds. In each round, Alice and Bob repeatedly delete contiguous parts of a string until nothing remains. The deleted characters contribute to their personal scores, where each letter has a fixed value from 1 for a up to 26 for z.