Codeforces Round 1045 (Div. 2)

6 problems from Codeforces Round 1045 (Div. 2) (contest 2134), difficulty 800-2900. 2/6 solutions verified against sample I/O.

6 items

Codeforces Round 1045 (Div. 2)

Div. 2 | 6 problems | 2/6 verified | Difficulty 800-2900 | 8m 56s

# Problem Rating Tags Accepted Time ✓
A Painting With Two Colors 800 constructive-algorithms, implementation, math 26,546 1m 43s
B Add 0 or K 1200 constructive-algorithms, math, number-theory 20,857 1m 40s
C Even Larger 1200 brute-force, greedy, implementation 18,667 1m 47s ✓
D Sliding Tree 2300 constructive-algorithms, dfs-and-similar, greedy 3,641 1m 30s
E Power Boxes 2300 constructive-algorithms, dp, implementation 2,396 1m 18s
F Permutation Oddness 2900 combinatorics, dp, math 647 58s ✓
Practice › Codeforces Solutions › Codeforces Round 1045 (Div. 2) ›

CF 2134D - Sliding Tree

We are given a tree and a very specific local rewiring operation. The operation picks a vertex $b$ with two distinguished neighbors $a$ and $c$. After that, every other neighbor of $b$ is detached from $b$ and reattached to $c$.
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Practice › Codeforces Solutions › Codeforces Round 1045 (Div. 2) ›

CF 2134E - Power Boxes

We are given a sequence of boxes, each with a hidden power of either 1 or 2. The boxes are placed on a number line at positions 1 through n. We need to discover the power of each box using two interactive queries: swapping adjacent boxes and throwing a ball at a box.
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Practice › Codeforces Solutions › Codeforces Round 1045 (Div. 2) ›

CF 2134F - Permutation Oddness

We are given counts for four integers, 0 through 3. Specifically, $c0$ copies of 0, $c1$ copies of 1, $c2$ copies of 2, and $c3$ copies of 3. From this, we can form an array of length $n = c0 + c1 + c2 + c3$.
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CF 2134C - Even Larger

We are given an array of non-negative integers and we need to make it good by performing the minimum number of operations.
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CF 2134A - Painting With Two Colors

We are given a row of n cells, all initially white. We have two painting operations. The first operation paints a consecutive cells red, starting at any position x such that the red block fits entirely within the row.
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Practice › Codeforces Solutions › Codeforces Round 1045 (Div. 2) ›

CF 2134B - Add 0 or K

We are given an array of positive integers and a positive integer $k$. For each element of the array, we are allowed to either leave it as-is or add $k$ to it in one operation.
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