Codeforces Round 774 (Div. 2)

6 problems from Codeforces Round 774 (Div. 2) (contest 1646), difficulty 800-2900. 6/6 solutions verified against sample I/O.

6 items

Codeforces Round 774 (Div. 2)

Div. 2 | 6 problems | 6/6 verified | Difficulty 800-2900 | 28m 42s

# Problem Rating Tags Accepted Time ✓
A Square Counting 800 math 25,386 1m 26s ✓
B Quality vs Quantity 800 brute-force, constructive-algorithms, greedy 22,665 1m 16s ✓
C Factorials and Powers of Two 1500 bitmasks, brute-force, constructive-algorithms 19,508 1m 28s ✓
D Weight the Tree 2000 constructive-algorithms, dfs-and-similar, dp 4,442 3m 56s ✓
E Power Board 2200 brute-force, dp, math 2,757 5m ✓
F Playing Around the Table 2900 constructive-algorithms, greedy, implementation 671 15m 36s ✓
Practice › Codeforces Solutions › Codeforces Round 774 (Div. 2) ›

CF 1646F - Playing Around the Table

We are given a circular arrangement of $n$ players, each holding exactly $n$ cards. Every card carries a label from $1$ to $n$, and each label appears exactly $n$ times across the whole system.
codeforces competitive-programming constructive-algorithms greedy implementation Jun 15, 2026
Practice › Codeforces Solutions › Codeforces Round 774 (Div. 2) ›

CF 1646E - Power Board

We are looking at a grid where each position is completely deterministic: the cell in row $i$ and column $j$ contains the value $i^j$.
codeforces competitive-programming brute-force dp math number-theory Jun 14, 2026
Practice › Codeforces Solutions › Codeforces Round 774 (Div. 2) ›

CF 1646D - Weight the Tree

We are given a tree, and we must assign a positive integer weight to every vertex. A vertex is called good if its weight equals the sum of the weights of all vertices adjacent to it. The goal is not just to satisfy this condition arbitrarily.
codeforces competitive-programming constructive-algorithms dfs-and-similar dp implementation trees Jun 14, 2026
Practice › Codeforces Solutions › Codeforces Round 774 (Div. 2) ›

CF 1646C - Factorials and Powers of Two

We are given a number and asked to express it as a sum of distinct “building blocks”. Each building block must be either a power of two or a factorial value.
codeforces competitive-programming bitmasks brute-force constructive-algorithms dp math Jun 10, 2026
Practice › Codeforces Solutions › Codeforces Round 774 (Div. 2) ›

CF 1646A - Square Counting

We are given a sequence of length $n+1$. Each element is either a “small” number in the range $[0, n-1]$, or a special large value equal to $n^2$. We are told only two things: the parameter $n$ and the total sum of all elements in the sequence, denoted $s$.
codeforces competitive-programming math Jun 10, 2026
Practice › Codeforces Solutions › Codeforces Round 774 (Div. 2) ›

CF 1646B - Quality vs Quantity

We are given a sequence of non-negative integers, and we can paint each element red, blue, or leave it unpainted.
codeforces competitive-programming brute-force constructive-algorithms greedy sortings two-pointers Jun 10, 2026