Codeforces Round 247 (Div. 2)

5 problems from Codeforces Round 247 (Div. 2) (contest 431), difficulty 800-2200. 5/5 solutions verified against sample I/O.

5 items

Codeforces Round 247 (Div. 2)

Div. 2 | 5 problems | 5/5 verified | Difficulty 800-2200 | 8m 37s

# Problem Rating Tags Accepted Time ✓
A Black Square 800 implementation 65,916 1m 10s ✓
B Shower Line 1200 brute-force, implementation 11,670 1m 52s ✓
C k-Tree 1600 dp, implementation, trees 29,771 1m 31s ✓
D Random Task 2100 binary-search, bitmasks, combinatorics 2,873 2m 1s ✓
E Chemistry Experiment 2200 binary-search, data-structures, ternary-search 1,187 2m 3s ✓
Practice › Codeforces Solutions › Codeforces Round 247 (Div. 2) ›

CF 431A - Black Square

In "Black Square," Jury must press on one of four vertical strips whenever a black square appears. Each strip has a fixed energy cost, measured in calories, for pressing it.
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CF 431B - Shower Line

We have exactly five students standing in a line for a shower. While one student is showering, the remaining students wait in line and talk in adjacent pairs. The first and second students talk, the third and fourth students talk, and so on.
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CF 431C - k-Tree

We are working with a rooted infinite tree where every node always has exactly $k$ outgoing edges to children. Each of those $k$ edges has a fixed weight: the first is 1, the second is 2, and so on up to $k$.
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CF 431D - Random Task

We need to find a positive integer n such that inside the interval (n, 2n], exactly m numbers have exactly k ones in their binary representation.
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CF 431E - Chemistry Experiment

We are given a set of containers, each containing some fixed amount of mercury. Over time, two kinds of operations happen. The first operation changes the mercury amount in a single container.
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