Recursion with Backtracking in Python

tip

Yet one more reminder

recursion/backtracking-template.py

def backtrack(candidate):
    if is_solution(candidate):
        output(candidate)
        return

    for next_candidate in list_of_candidates:
        if is_valid(next_candidate):
            place(next_candidate)
            backtrack(next_candidate)
            remove(next_candidate)