Educational Codeforces Round 120 (Rated for Div. 2)

Solutions for Educational Codeforces Round 120 (Rated for Div. 2) (contest 1622). 2/6 problems verified against sample I/O. Difficulty range: 800-2900.

6 items

Educational Codeforces Round 120 (Rated for Div. 2)

Type: Div. 2 | Problems: 6 | Verified: 2/6 | Rating range: 800-2900 | Time: 16m

Problem Name Rating Tags Solve Time Verified
A Construct a Rectangle 800 geometry, math 1m 17s ✓
B Berland Music 1000 data-structures, greedy, math 7m 19s ✗
C Set or Decrease 1600 binary-search, brute-force, greedy 1m 39s ✗
D Shuffle 2000 combinatorics, math, two-pointers 3m 12s ✗
E Math Test 2200 bitmasks, brute-force, greedy 1m 22s ✗
F Quadratic Set 2900 constructive-algorithms, hashing, math 1m 11s ✓
Practice › Codeforces Solutions › Educational Codeforces Round 120 (Rated for Div. 2) ›

CF 1622B - Berland Music

I see exactly what is happening here. The root cause is not a bug in the algorithm for Codeforces 1628C; it is that the input you are feeding to the Python program does not match the expected input format of the problem.
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Practice › Codeforces Solutions › Educational Codeforces Round 120 (Rated for Div. 2) ›

CF 1622D - Shuffle

We are given a binary string, a sequence of 0s and 1s, and an integer $k$. We are allowed to select at most one contiguous substring that contains exactly $k$ ones and then arbitrarily rearrange the characters of that substring.
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Practice › Codeforces Solutions › Educational Codeforces Round 120 (Rated for Div. 2) ›

CF 1622F - Quadratic Set

We are given the set of integers from 1 to n, and we are allowed to choose any subset of these numbers. For a chosen subset, we compute the product of factorials of all selected elements. A subset is considered valid when this product becomes a perfect square.
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Practice › Codeforces Solutions › Educational Codeforces Round 120 (Rated for Div. 2) ›

CF 1622E - Math Test

We are given a set of students who have taken a math test with multiple questions. Each student answered some questions correctly and some incorrectly.
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Practice › Codeforces Solutions › Educational Codeforces Round 120 (Rated for Div. 2) ›

CF 1622C - Set or Decrease

We are given an array of integers and want to reduce its total sum until it becomes no larger than a target value. The only allowed actions are either decreasing a single element by one unit, or copying the value of one element into another position.
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Practice › Codeforces Solutions › Educational Codeforces Round 120 (Rated for Div. 2) ›

CF 1622A - Construct a Rectangle

We are given three sticks of integer lengths, and we are allowed to cut exactly one stick into two positive integer-length pieces. After this cut, we will have four sticks in total.
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