Codeforces Beta Round 52 (Div. 2)

5 problems from Codeforces Beta Round 52 (Div. 2) (contest 56), difficulty 1000-2200. 5/5 solutions verified against sample I/O.

5 items

Codeforces Beta Round 52 (Div. 2)

Div. 2 | 5 problems | 5/5 verified | Difficulty 1000-2200 | 8m 47s

# Problem Rating Tags Accepted Time ✓
A Bar 1000 implementation 9,636 1m 28s ✓
B Spoilt Permutation 1300 implementation 4,023 1m 42s ✓
C Corporation Mail 1700 data-structures, expression-parsing, implementation 1,305 1m 33s ✓
D Changing a String 2100 dp 2,087 2m 12s ✓
E Domino Principle 2200 binary-search, data-structures, sortings 2,837 1m 52s ✓
Practice › Codeforces Solutions › Codeforces Beta Round 52 (Div. 2) ›

CF 56A - Bar

Vasya walks into a bar and sees several customers. For each customer, he only knows one piece of information: either the person’s age or the drink they ordered. He wants to determine how many people must still be checked to guarantee that nobody under 18 is drinking alcohol.
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Practice › Codeforces Solutions › Codeforces Beta Round 52 (Div. 2) ›

CF 56B - Spoilt Permutation

We start from the sorted permutation 1 2 3 ... n. Someone chooses exactly one contiguous segment and reverses it. We are given the final permutation and must determine whether it could have been produced by exactly one such reversal. The task is not to sort the array.
codeforces competitive-programming implementation May 28, 2026
Practice › Codeforces Solutions › Codeforces Beta Round 52 (Div. 2) ›

CF 56C - Corporation Mail

The problem presents a company hierarchy encoded as a string. Each employee has a name, followed optionally by a colon and a comma-separated list of subordinates, ending with a dot. If an employee has no subordinates, the colon is omitted.
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Practice › Codeforces Solutions › Codeforces Beta Round 52 (Div. 2) ›

CF 56D - Changing a String

We are given two uppercase strings, s and t. We may transform s using three operations: 1. Insert a character at any position. 2. Delete a character from any position. 3. Replace one character with another. Every operation costs exactly one move.
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Practice › Codeforces Solutions › Codeforces Beta Round 52 (Div. 2) ›

CF 56E - Domino Principle

We have dominoes placed on a number line. Each domino stands at coordinate x[i] and has height h[i]. If a domino falls to the right, it reaches every point from x[i] + 1 up to x[i] + h[i] - 1.
codeforces competitive-programming binary-search data-structures sortings May 28, 2026