Codeforces Round 506 (Div. 3)

6 problems from Codeforces Round 506 (Div. 3) (contest 1029), difficulty 1200-2100. 5/6 solutions verified against sample I/O.

6 items

Codeforces Round 506 (Div. 3)

Div. 3 | 6 problems | 5/6 verified | Difficulty 1200-2100 | 22m 31s

# Problem Rating Tags Accepted Time ✓
A Many Equal Substrings 1300 implementation, strings 13,430 2m 24s ✓
B Creating the Contest 1200 dp, greedy, math 18,462 2m 25s ✓
C Maximal Intersection 1600 greedy, math, sortings 8,272 2m 50s ✓
D Concatenated Multiples 1900 implementation, math 4,234 5m 17s
E Tree with Small Distances 2100 dp, graphs, greedy 3,415 5m 54s ✓
F Multicolored Markers 2000 binary-search, brute-force, math 2,754 3m 41s ✓
Practice › Codeforces Solutions › Codeforces Round 506 (Div. 3) ›

CF 1029E - Tree with Small Distances

We are given a tree where vertex 1 plays a special role: it is the root of our concern. The structure is initially fixed, but we are allowed to add new edges between any two previously unconnected vertices.
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Practice › Codeforces Solutions › Codeforces Round 506 (Div. 3) ›

CF 1029D - Concatenated Multiples

We are given a list of positive integers and a modulus $k$. For every ordered pair of distinct indices $(i, j)$, we form a new number by writing $ai$ directly followed by $aj$ in decimal representation. We need to count how many such ordered concatenations are divisible by $k$.
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Practice › Codeforces Solutions › Codeforces Round 506 (Div. 3) ›

CF 1029F - Multicolored Markers

We are given two counts, $a$ red tiles and $b$ blue tiles, and we must place them on an infinite grid so that all colored tiles together form a single axis-aligned rectangle of area $a+b$.
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Practice › Codeforces Solutions › Codeforces Round 506 (Div. 3) ›

CF 1029C - Maximal Intersection

We are given a collection of segments on a number line, and we want to understand how much they overlap if we remove exactly one of them.
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Practice › Codeforces Solutions › Codeforces Round 506 (Div. 3) ›

CF 1029B - Creating the Contest

We are given a sorted list of distinct problem difficulties. From this list, we must choose a subsequence, not necessarily contiguous, that will form a contest.
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Practice › Codeforces Solutions › Codeforces Round 506 (Div. 3) ›

CF 1029A - Many Equal Substrings

We are given a pattern string t of length n and a target number k. We need to build a new string s as short as possible such that when we slide a window of length n across s, the pattern t appears exactly k times as a substring.
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