Codeforces Beta Round 88

5 problems from Codeforces Beta Round 88 (contest 117), difficulty 1300-2900. 5/5 solutions verified against sample I/O.

5 items

Codeforces Beta Round 88

Beta | 5 problems | 5/5 verified | Difficulty 1300-2900 | 13m 35s

# Problem Rating Tags Accepted Time ✓
A Elevator 1300 implementation, math 2,225 2m 31s ✓
B Very Interesting Game 1800 brute-force, number-theory 1,743 2m 31s ✓
C Cycle 2000 dfs-and-similar, graphs 2,962 3m ✓
D Not Quick Transformation 2500 divide-and-conquer, math 369 2m 20s ✓
E Tree or not Tree 2900 data-structures, divide-and-conquer, graphs 414 3m 13s ✓
Practice › Codeforces Solutions › Codeforces Beta Round 88 ›

CF 117A - Elevator

The elevator follows a completely deterministic cycle. It starts at floor 1 at time 0, climbs one floor per second until it reaches floor m, then immediately reverses direction and goes back down to floor 1, again moving one floor per second.
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CF 117B - Very Interesting Game

We are asked to simulate a two-player game involving numbers represented as nine-digit strings. The first player selects a string s1 that represents a number not exceeding a given value a. The second player responds with a string s2 representing a number not exceeding b.
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CF 117C - Cycle

We are given a tournament graph, which is a special type of directed graph where for every pair of distinct vertices, there is exactly one directed edge connecting them.
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CF 117D - Not Quick Transformation

We start with the array [1, 2, 3, ..., n]. A recursive transformation rearranges it by repeatedly taking all elements at odd positions, transforming that subarray, then taking all elements at even positions and transforming that subarray.
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CF 117E - Tree or not Tree

The graph has exactly n vertices and n edges. A connected graph with n vertices and n edges contains exactly one simple cycle. Every other edge belongs to a tree attached to that cycle. Initially every edge is turned off.
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