Backtracking / Recursive Search / Constraint Pruning
These visualizers focus on reversible decisions: choose, recurse, inspect the branch, and then undo the move so the search can try the next possibility without carrying stale state forward.
Trace the Combination Sum algorithm from parsed input through each decision point.
Trace the Combinations algorithm from parsed input through each decision point.
Trace the Generate Parentheses algorithm from parsed input through each decision point.
Trace the Letter Combinations of a Phone Number algorithm from parsed input through each decision point.
Trace the N-Queens II algorithm from parsed input through each decision point.
Fill the next slot with one unused value, recurse until every slot is occupied, then undo the placement so a different ordering can be explored cleanly.
Try each board cell as a start, walk orthogonal neighbors that match the next character, and backtrack the path the moment a branch cannot continue the word.