This pattern partition at every index Processed part , perform operations asked in the question. Unprocessed part -> will again pass in…

permutations processed unprocessed simple

At every step you have two option, either take or not take. For take you have to write some condition for which you choose the take the…

At every step you have many options, not just two. Try each one, but only if it is safe (no clash with what is already placed). Recurse on…