Educational Codeforces Round 151 (Rated for Div. 2)

Solutions for Educational Codeforces Round 151 (Rated for Div. 2) (contest 1845). 2/6 problems verified against sample I/O. Difficulty range: 800-2800.

6 items

Educational Codeforces Round 151 (Rated for Div. 2)

Type: Div. 2 | Problems: 6 | Verified: 2/6 | Rating range: 800-2800 | Time: 12m 50s

Problem	Name	Rating	Tags	Solve Time	Verified
A	Forbidden Integer	800	constructive-algorithms, implementation, math	5m 13s	✗
B	Come Together	900	geometry, implementation, math	1m 22s	✓
C	Strong Password	1400	binary-search, dp, greedy	1m 19s	✗
D	Rating System	1800	binary-search, brute-force, data-structures	1m 38s	✗
E	Boxes and Balls	2500	dp, implementation, math	1m 43s	✗
F	Swimmers in the Pool	2800	dp, fft, math	1m 35s	✓

Practice › Codeforces Solutions › Educational Codeforces Round 151 (Rated for Div. 2) ›

CF 1845A - Forbidden Integer

We are asked to determine whether a target sum n can be formed using any number of integers from 1 to k, excluding a single forbidden integer x. If it is possible, we must construct one valid sequence of integers whose sum is exactly n.

Practice › Codeforces Solutions › Educational Codeforces Round 151 (Rated for Div. 2) ›

CF 1845F - Swimmers in the Pool

We have a pool of length $l$ and $n$ swimmers. Each swimmer starts at the same time from one end and moves to the other at a constant speed $vi$. Upon reaching the far end, they immediately turn around and continue swimming back and forth indefinitely.

Practice › Codeforces Solutions › Educational Codeforces Round 151 (Rated for Div. 2) ›

CF 1845E - Boxes and Balls

We are given a row of n boxes, some containing a ball and some empty. The allowed operation is to move a ball from a box into an adjacent empty box, with adjacency defined as consecutive indices.

Practice › Codeforces Solutions › Educational Codeforces Round 151 (Rated for Div. 2) ›

CF 1845D - Rating System

We are simulating a rating that starts at zero and is updated after each match by adding an integer delta from an array. Positive values increase the rating, negative values decrease it. There is an extra constraint controlled by a parameter $k$.

Practice › Codeforces Solutions › Educational Codeforces Round 151 (Rated for Div. 2) ›

CF 1845B - Come Together

We are working on a grid where two people, Bob and Carol, start from the same cell and must travel to their own destinations using shortest paths in Manhattan distance.

Practice › Codeforces Solutions › Educational Codeforces Round 151 (Rated for Div. 2) ›

CF 1845C - Strong Password

We are asked to determine whether Monocarp can construct a password of exactly length m that satisfies three conditions: each digit must lie between the corresponding digits of two strings l and r, the password must only use digits 0 through 9, and it must not appear as a…