Educational Codeforces Round 140 (Rated for Div. 2)

Solutions for Educational Codeforces Round 140 (Rated for Div. 2) (contest 1767). 1/6 problems verified against sample I/O. Difficulty range: 800-3100.

6 items

Educational Codeforces Round 140 (Rated for Div. 2)

Type: Div. 2 | Problems: 6 | Verified: 1/6 | Rating range: 800-3100 | Time: 19m 17s

Problem Name Rating Tags Solve Time Verified
A Cut the Triangle 800 implementation 6m 56s ✗
B Block Towers 800 data-structures, greedy, sortings 2m 2s ✗
C Count Binary Strings 2100 data-structures, dp 2m 9s ✗
D Playoff 1500 combinatorics, constructive-algorithms, dp 4m 9s ✗
E Algebra Flash 2500 bitmasks, brute-force, dp 1m 45s ✓
F Two Subtrees 3100 data-structures, trees 2m 16s ✗
Practice › Codeforces Solutions › Educational Codeforces Round 140 (Rated for Div. 2) ›

CF 1767A - Cut the Triangle

The problem gives a triangle in the plane with positive area, specified by three points with integer coordinates.
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CF 1767D - Playoff

We are looking at a tournament structured as a perfect binary tree. At the start there are $2^n$ teams, each assigned a distinct skill value from 1 to $2^n$.
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CF 1767F - Two Subtrees

We are given a rooted tree where every vertex stores an integer label. For each query, we are given two vertices, and we must look at two subtrees rooted at these vertices.
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CF 1767E - Algebra Flash

We are given a linear sequence of platforms, each with a fixed color, and a cost associated with activating all platforms of each color. Initially, all platforms are deactivated. You can only jump from a platform to the next one or skip one to the platform after that.
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CF 1767C - Count Binary Strings

We are given an $n times n$ upper-triangular table of constraints on substrings of a binary string $s$ of length $n$. For every interval $[i, j]$, we are told whether that segment must be constant, must contain both 0 and 1, or is unconstrained.
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Practice › Codeforces Solutions › Educational Codeforces Round 140 (Rated for Div. 2) ›

CF 1767B - Block Towers

We are given several towers, each containing a certain number of blocks. The goal is to maximize the number of blocks on the first tower by moving blocks from towers that have more blocks than others.
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