Codeforces Round 525 (Div. 2)

6 problems from Codeforces Round 525 (Div. 2) (contest 1088), difficulty 800-2800. 3/6 solutions verified against sample I/O.

6 items

Codeforces Round 525 (Div. 2)

Div. 2 | 6 problems | 3/6 verified | Difficulty 800-2800 | 26m

#	Problem	Rating	Tags	Accepted	Time	✓
A	Ehab and another construction problem	800	brute-force, constructive-algorithms	17,635	3m 4s
B	Ehab and subtraction	1000	implementation, sortings	13,584	2m 53s
C	Ehab and a 2-operation task	1400	constructive-algorithms, greedy, math	8,517	2m 56s	✓
D	Ehab and another another xor problem	2000	bitmasks, constructive-algorithms, implementation	3,168	6m 30s
E	Ehab and a component choosing problem	2400	dp, greedy, math	1,616	6m 39s	✓
F	Ehab and a weird weight formula	2800	data-structures, trees	597	3m 58s	✓

Practice › Codeforces Solutions › Codeforces Round 525 (Div. 2) ›

CF 1088E - Ehab and a component choosing problem

We are given a weighted tree, where every node carries an integer value that can be positive, negative, or zero. The task is to select some nodes and partition the selected nodes into several connected components.

Practice › Codeforces Solutions › Codeforces Round 525 (Div. 2) ›

CF 1088D - Ehab and another another xor problem

We are trying to determine two hidden integers, a and b, each less than $2^{30}$. We cannot see them directly. Instead, we are allowed to query pairs $(c, d)$, and the judge compares the values $a oplus c$ and $b oplus d$, returning whether the first is greater, equal, or…

Practice › Codeforces Solutions › Codeforces Round 525 (Div. 2) ›

CF 1088F - Ehab and a weird weight formula

We are given a set of nodes, each carrying a fixed positive weight. The task is not to compute anything on a given tree, but to design a tree structure on these nodes so that a certain cost expression becomes as small as possible. Two constraints shape the construction.

Practice › Codeforces Solutions › Codeforces Round 525 (Div. 2) ›

CF 1088A - Ehab and another construction problem

We are given a small integer $x$, and we need to construct two integers $a$ and $b$, both constrained to lie between 1 and $x$, such that a few arithmetic conditions hold simultaneously. First, $b$ must divide $a$, meaning $a$ is an exact multiple of $b$.

Practice › Codeforces Solutions › Codeforces Round 525 (Div. 2) ›

CF 1088C - Ehab and a 2-operation task

We are given a sequence of integers and allowed to repeatedly apply operations that affect prefixes of the array.

Practice › Codeforces Solutions › Codeforces Round 525 (Div. 2) ›

CF 1088B - Ehab and subtraction

We are repeatedly performing a global “level reduction” on an array. At each step, we look at all positive values currently present, identify the smallest among them, output that value, and then reduce every positive element by that same amount.