Codeforces Round 905 (Div. 1)

Solutions for Codeforces Round 905 (Div. 1) (contest 1887). 2/5 problems verified against sample I/O. Difficulty range: 1900-3400.

5 items

Codeforces Round 905 (Div. 1)

Type: Div. 1 | Problems: 5 | Verified: 2/5 | Rating range: 1900-3400 | Time: 9m 52s

Problem Name Rating Tags Solve Time Verified
B Time Travel 1900 binary-search, graphs, shortest-paths 1m 25s ✓
C Minimum Array 2400 binary-search, brute-force, constructive-algorithms 2m 2s ✗
D Split 2700 binary-search, data-structures, divide-and-conquer 2m 5s ✓
E Good Colorings 3100 binary-search, constructive-algorithms, graphs 2m 16s ✗
F Minimum Segments 3400 constructive-algorithms 2m 4s ✗
Practice › Codeforces Solutions › Codeforces Round 905 (Div. 1) ›

CF 1887F - Minimum Segments

We are given a sequence of integers r1, r2, ..., rn, called the characteristic of some unknown sequence a1, a2, ..., an of length n.
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CF 1887E - Good Colorings

We are asked to interact with a grid of size $n times n$. Initially, $2n$ cells are pre-colored with unique colors from $1$ to $2n$, and the rest are uncolored. In each of up to 10 allowed moves, we can request Alice to color a previously uncolored cell.
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Practice › Codeforces Solutions › Codeforces Round 905 (Div. 1) ›

CF 1887D - Split

We are given an array of distinct integers ranging from 1 to n, and we are asked to answer multiple queries about contiguous subarrays.
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CF 1887C - Minimum Array

We are given an array of integers and a sequence of operations that increment segments of the array by a given value. Each operation specifies a contiguous subarray and an integer to add.
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CF 1887B - Time Travel

We are given a fixed set of cities and a sequence of historical snapshots. Each snapshot describes which roads exist between cities at that moment in time. These road systems change completely from one snapshot to another.
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