Community Problem
Beautiful Arrangement
Difficulty: Medium
Count the permutations of 1..n where every i either divides perm[i] or is divided by perm[i], using backtracking with divisibility pruning.
Community Problem
Difficulty: Medium
Count the permutations of 1..n where every i either divides perm[i] or is divided by perm[i], using backtracking with divisibility pruning.