Codeforces Round 847 (Div. 3)

Solutions for Codeforces Round 847 (Div. 3) (contest 1790). 2/7 problems verified against sample I/O. Difficulty range: 800-2300.

7 items

Codeforces Round 847 (Div. 3)

Type: Div. 3 | Problems: 7 | Verified: 2/7 | Rating range: 800-2300 | Time: 14m 9s

Problem	Name	Rating	Tags	Solve Time	Verified
A	Polycarp and the Day of Pi	800	implementation, math, strings	1m 35s	✓
B	Taisia and Dice	800	greedy, math	1m 45s	✗
C	Premutation	1000	brute-force, implementation, math	1m 46s	✗
D	Matryoshkas	1200	data-structures, greedy, sortings	1m 51s	✓
E	Vlad and a Pair of Numbers	1400	bitmasks, constructive-algorithms	2m 41s	✗
F	Timofey and Black-White Tree	2100	brute-force, dfs-and-similar, divide-and-conquer	1m 58s	✗
G	Tokens on Graph	2300	constructive-algorithms, dfs-and-similar, graphs	2m 33s	✗

Practice › Codeforces Solutions › Codeforces Round 847 (Div. 3) ›

CF 1790G - Tokens on Graph

We are given a connected undirected graph where certain vertices contain tokens and certain vertices contain bonuses. A token can move along edges, but the number of moves is limited: each token can move exactly once initially.

Practice › Codeforces Solutions › Codeforces Round 847 (Div. 3) ›

CF 1790E - Vlad and a Pair of Numbers

The problem asks us to find two positive integers, a and b, given a number x, such that two conditions hold simultaneously: a XOR b = x and (a + b)/2 = x.

Practice › Codeforces Solutions › Codeforces Round 847 (Div. 3) ›

CF 1790F - Timofey and Black-White Tree

We are given a tree where one vertex starts as black and every other vertex is initially white. Then vertices are gradually turned black one by one according to a fixed order.

Practice › Codeforces Solutions › Codeforces Round 847 (Div. 3) ›

CF 1790D - Matryoshkas

We are given a collection of matryoshka dolls, all mixed together, and each doll has a positive integer size. Each original set consisted of dolls of consecutive sizes, and each set was used entirely.

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CF 1790C - Premutation

We are given several test cases. In each test case there exists a hidden permutation of numbers from 1 to n. Instead of seeing the permutation directly, we are given n derived arrays.

Practice › Codeforces Solutions › Codeforces Round 847 (Div. 3) ›

CF 1790B - Taisia and Dice

We are asked to reconstruct the results of rolling multiple six-sided dice when some summary information is missing. Specifically, Taisia rolls $n$ dice, and the sum of all dice is $s$.

Practice › Codeforces Solutions › Codeforces Round 847 (Div. 3) ›

CF 1790A - Polycarp and the Day of Pi

Each test case gives a string of digits that Polycarp wrote down after trying to memorize the digits of π. The task is to determine how many leading digits of π match the prefix of this string. We are not reconstructing π or correcting errors.