Codeforces Round 633 (Div. 1)

3 problems from Codeforces Round 633 (Div. 1) (contest 1338), difficulty 1500-2700. 2/3 solutions verified against sample I/O.

3 items

Codeforces Round 633 (Div. 1)

Div. 1 | 3 problems | 2/3 verified | Difficulty 1500-2700 | 15m 48s

# Problem Rating Tags Accepted Time ✓
A Powered Addition 1500 greedy, math 30,333 2m 29s ✓
C Perfect Triples 2200 bitmasks, brute-force, constructive-algorithms 3,440 6m 54s
D Nested Rubber Bands 2700 constructive-algorithms, dfs-and-similar, dp 1,127 6m 25s ✓
Practice › Codeforces Solutions › Codeforces Round 633 (Div. 1) ›

CF 1338C - Perfect Triples

We are building an infinite sequence by repeatedly selecting groups of three unused positive integers. Each group must satisfy a strict bitwise condition: the XOR of the three numbers is zero.
codeforces competitive-programming bitmasks brute-force constructive-algorithms divide-and-conquer math Jun 16, 2026
Practice › Codeforces Solutions › Codeforces Round 633 (Div. 1) ›

CF 1338D - Nested Rubber Bands

We are given a tree, and the problem asks us to think about a geometric construction that can be performed on it. Each vertex becomes a closed non-self-intersecting curve on a plane.
codeforces competitive-programming constructive-algorithms dfs-and-similar dp math trees Jun 16, 2026
Practice › Codeforces Solutions › Codeforces Round 633 (Div. 1) ›

CF 1338A - Powered Addition

We are given an integer array and we are allowed to repeatedly perform timed operations. In the $x$-th second, we may choose any subset of indices and add the same value $2^{x-1}$ to all chosen positions.
codeforces competitive-programming greedy math Jun 11, 2026