VK Cup 2019-2020 - Elimination Round (Engine)

5 problems from VK Cup 2019-2020 - Elimination Round (Engine) (contest 1310), difficulty 1700-3400. 0/5 solutions verified against sample I/O.

5 items

VK Cup 2019-2020 - Elimination Round (Engine)

Special | 5 problems | 0/5 verified | Difficulty 1700-3400 | 25m 3s

# Problem Rating Tags Accepted Time ✓
A Recommendations 1700 data-structures, greedy, sortings 5,582 5m 50s
B Double Elimination 2500 dp, implementation 574 59s
C Au Pont Rouge 2800 binary-search, dp, strings 730 1m 30s
D Tourism 2300 dp, graphs, probabilities 1,986 14m 40s
F Bad Cryptography 3400 math, number-theory 103 2m 4s
Practice › Codeforces Solutions › VK Cup 2019-2020 - Elimination Round (Engine) ›

CF 1310D - Tourism

We are given a complete directed graph of cities where every ordered pair of distinct cities has a travel cost. Starting from city 1, we must perform exactly $k$ moves, and end again at city 1. Each move is just choosing a directed edge and paying its cost.
codeforces competitive-programming dp graphs probabilities Jun 16, 2026
Practice › Codeforces Solutions › VK Cup 2019-2020 - Elimination Round (Engine) ›

CF 1310B - Double Elimination

We are given a full double elimination tournament with $2^n$ teams, where the bracket structure is completely fixed.
codeforces competitive-programming dp implementation Jun 16, 2026
Practice › Codeforces Solutions › VK Cup 2019-2020 - Elimination Round (Engine) ›

CF 1310A - Recommendations

Codeforces 1310A: Recommendations
codeforces competitive-programming data-structures greedy sortings Jun 11, 2026
Practice › Codeforces Solutions › VK Cup 2019-2020 - Elimination Round (Engine) ›

CF 1310F - Bad Cryptography

Yes, the inequality $nu(n) le 2^{l(n) - lambda(n)}$ holds for all positive integers $n$. Consider an addition chain of minimal length $l(n)$ and let $lambda(n)$ be the length of a shortest chain consisting only of doubling steps.
codeforces competitive-programming math number-theory Jun 11, 2026
Practice › Codeforces Solutions › VK Cup 2019-2020 - Elimination Round (Engine) ›

CF 1310C - Au Pont Rouge

Yes, the inequality $nu(n) le 2^{l(n) - lambda(n)}$ holds for all positive integers $n$. Consider an addition chain of minimal length $l(n)$ and let $lambda(n)$ be the length of a shortest chain consisting only of doubling steps.
codeforces competitive-programming binary-search dp strings Jun 11, 2026