D - An Invisible Hand

C - 1D Reversi

B - Snuke’s Coloring 2 (ABC Edit)

Codeforces Round #628 (Div. 2) C. Ehab and Path-etic MEXs

Codeforces Global Round 7 D2. Prefix-Suffix Palindrome (Hard version)

Codeforces Global Round 7 D1. Prefix-Suffix Palindrome (Easy version)

Codeforces Round #630 (Div. 2) C. K-Complete Word

Codeforces Round #633 (Div. 1) A. Powered Addition

Codeforces Round #637 (Div. 1) - Thanks, Ivan Belonogov! A. Nastya and Strange Generator

1238. Circular Permutation in Binary Representation

Given 2 integers n and start. Your task is return any permutation p of (0,1,2…..,2^n -1) such that :

• p[0] = start
• p[i] and p[i+1] differ by only one bit in their binary representation.
• p[0] and p[2^n -1] must also differ by only one bit in their binary representation.