Educational Codeforces Round 148 (Rated for Div. 2)

Solutions for Educational Codeforces Round 148 (Rated for Div. 2) (contest 1832). 3/7 problems verified against sample I/O. Difficulty range: 800-3200.

7 items

Educational Codeforces Round 148 (Rated for Div. 2)

Type: Div. 2 | Problems: 7 | Verified: 3/7 | Rating range: 800-3200 | Time: 13m 2s

Problem Name Rating Tags Solve Time Verified
A New Palindrome 800 strings 1m 31s ✗
B Maximum Sum 1100 brute-force, sortings, two-pointers 1m 22s ✓
C Contrast Value 1200 greedy, implementation 3m 27s ✓
D1 Red-Blue Operations (Easy Version) 2100 binary-search, greedy, implementation 1m 41s ✗
D2 Red-Blue Operations (Hard Version) 2400 binary-search, constructive-algorithms, greedy 1m 37s ✗
E Combinatorics Problem 2200 brute-force, combinatorics, dp 1m 40s ✓
F Zombies 3200 binary-search, dp 1m 44s ✗
Practice › Codeforces Solutions › Educational Codeforces Round 148 (Rated for Div. 2) ›

CF 1832F - Zombies

Each entrance in this problem behaves like a stream of zombies arriving over a long time interval. For every minute in the range $[0, x)$, exactly one zombie attempts to pass through each entrance.
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CF 1832E - Combinatorics Problem

We are asked to compute a transformed array from a pseudo-randomly generated sequence using binomial coefficients.
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CF 1832C - Contrast Value

We are given an array and a specific measure of how “change-heavy” it is: the sum of absolute differences between consecutive elements. This value captures how much the array oscillates as we walk through it left to right.
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CF 1832D2 - Red-Blue Operations (Hard Version)

We are given an array of integers, initially colored red. On each operation, you pick a single element. If it is red, you increase it by the operation number and switch it to blue. If it is blue, you decrease it by the operation number and switch it back to red.
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CF 1832D1 - Red-Blue Operations (Easy Version)

We have an array of integers, each initially painted red, and a sequence of operations numbered from one onwards. On operation number $i$, if we pick a red element, it increases by $i$ and turns blue; if we pick a blue element, it decreases by $i$ and turns red.
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Practice › Codeforces Solutions › Educational Codeforces Round 148 (Rated for Div. 2) ›

CF 1832A - New Palindrome

We are asked to determine whether a palindrome string can be rearranged to form a different palindrome. A palindrome is a string that reads the same forwards and backwards, like "abba" or "racecar".
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Practice › Codeforces Solutions › Educational Codeforces Round 148 (Rated for Div. 2) ›

CF 1832B - Maximum Sum

We are given an array of distinct integers and must perform exactly k deletion operations. In each operation we can either remove the largest element or remove the two smallest elements together.
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