Educational Codeforces Round 188 (Rated for Div. 2)

7 problems from Educational Codeforces Round 188 (Rated for Div. 2) (contest 2204), difficulty 800-2700. 2/7 solutions verified against sample I/O.

7 items

Educational Codeforces Round 188 (Rated for Div. 2)

Div. 2 | 7 problems | 2/7 verified | Difficulty 800-2700 | 13m 51s

# Problem Rating Tags Accepted Time ✓
A Passing the Ball 800 brute-force, implementation 21,694 3m 5s ✓
B Right Maximum 800 greedy 19,483 1m 34s ✓
C Spring 1000 math, number-theory 17,330 1m 37s
D Alternating Path 1400 constructive-algorithms, dfs-and-similar, graph-matchings 8,879 1m 50s
E Sum of Digits (and Again) 1800 brute-force, constructive-algorithms, math 4,772 1m 47s
F Sum of Fractions 2200 binary-search, brute-force, combinatorics 1,221 2m 16s
G Grid Path 2700 dp, graphs, matrices 402 1m 42s
Practice › Codeforces Solutions › Educational Codeforces Round 188 (Rated for Div. 2) ›

CF 2204F - Sum of Fractions

We are asked to repeatedly increase fractions of the form $1/bi$ either by incrementing the numerator or decreasing the denominator if it is larger than 1.
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CF 2204G - Grid Path

We are working on a rectangular grid where we start from the top-left cell and are allowed to walk using three moves: left, right, or down. There is no upward movement, which is the key structural restriction.
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CF 2204D - Alternating Path

We are given an undirected graph and asked to assign a direction to each edge such that some vertices become "beautiful".
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CF 2204E - Sum of Digits (and Again)

We are given a multiset of digits for each test case, and we are allowed to reorder them freely. The goal is to decide whether we can arrange these digits to match a very specific structured string generated from some positive integer x.
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CF 2204A - Passing the Ball

We are given a line of students arranged from left to right, and a ball that moves deterministically according to fixed rules.
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CF 2204C - Spring

Each test case describes three periodic visitors to a spring. Alice arrives every $a$ days, Bob every $b$ days, and Carol every $c$ days. On any day in the range from day $1$ to day $m$, some subset of them may arrive depending on divisibility of the day number.
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CF 2204B - Right Maximum

We are given an array of integers and asked to simulate a very specific removal process. In each operation, we look at the current array, find the maximum element, and if multiple elements share that maximum, we choose the rightmost one.
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