Codeforces Round 810 (Div. 1)

Solutions for Codeforces Round 810 (Div. 1) (contest 1710). 2/5 problems verified against sample I/O. Difficulty range: 1500-3400.

5 items

Codeforces Round 810 (Div. 1)

Type: Div. 1 | Problems: 5 | Verified: 2/5 | Rating range: 1500-3400 | Time: 19m 23s

Problem	Name	Rating	Tags	Solve Time	Verified
A	Color the Picture	1500	constructive-algorithms, greedy, math	2m 35s	✓
B	Rain	2100	binary-search, brute-force, data-structures	2m 37s	✗
C	XOR Triangle	2500	bitmasks, brute-force, constructive-algorithms	9m 39s	✗
D	Recover the Tree	3400	constructive-algorithms, trees	2m 37s	✗
E	Two Arrays	2400	binary-search, games, graph-matchings	1m 55s	✓

Practice › Codeforces Solutions › Codeforces Round 810 (Div. 1) ›

CF 1710C - XOR Triangle

We are asked to count triples of integers taken from a segment $[l, r]$ such that the indices are strictly increasing and the value of the least common multiple of the three numbers is at least as large as their sum. The input describes several independent ranges.

Practice › Codeforces Solutions › Codeforces Round 810 (Div. 1) ›

CF 1710D - Recover the Tree

We are given a tree with n vertices indexed from 1 to n. The problem does not provide the tree explicitly, but it provides information about all possible contiguous segments of vertex indices. A segment [l,r] is called good if the vertices {l, l+1, ...

Practice › Codeforces Solutions › Codeforces Round 810 (Div. 1) ›

CF 1710E - Two Arrays

The game takes place on a conceptual grid where each position is identified by a row index and a column index. Each row has a fixed value from array a, and each column has a fixed value from array b. If the game ends at a cell (r, c), the score is simply the sum a[r] + b[c].

Practice › Codeforces Solutions › Codeforces Round 810 (Div. 1) ›

CF 1710B - Rain

We are asked to model rainfall accumulation along an infinite integer line. Each day brings rain concentrated at a specific position, with intensity that decays linearly with distance.

Practice › Codeforces Solutions › Codeforces Round 810 (Div. 1) ›

CF 1710A - Color the Picture

We are asked to color an $n times m$ grid using $k$ pigments, each of which can color a limited number of cells. A picture is considered beautiful if every cell shares its color with at least three of its four toroidal neighbors.