Codeforces Round 869 (Div. 2)

Solutions for Codeforces Round 869 (Div. 2) (contest 1818). 1/2 problems verified against sample I/O. Difficulty range: 800-900.

2 items

Codeforces Round 869 (Div. 2)

Type: Div. 2 | Problems: 2 | Verified: 1/2 | Rating range: 800-900 | Time: 4m 14s

Problem Name Rating Tags Solve Time Verified
A Politics 800 greedy, implementation 3m 7s ✗
B Indivisible 900 constructive-algorithms 1m 7s ✓
Practice › Codeforces Solutions › Codeforces Round 869 (Div. 2) ›

CF 1818A - Politics

The “bug” shown in the latest failures is not algorithmic at all. It is a parsing assumption error: the solution is reading input as if every test case starts with two integers (n, k), or a single integer n, while the actual input format for this problem is different across…
codeforces competitive-programming greedy implementation Jun 9, 2026
Practice › Codeforces Solutions › Codeforces Round 869 (Div. 2) ›

CF 1818B - Indivisible

We are asked to construct a permutation of the integers from 1 to n such that for every subarray of length greater than one, the sum of the subarray is not divisible by its length.
codeforces competitive-programming constructive-algorithms Jun 9, 2026