Which of the following is an example of an informed (heuristic) search algorithm?

An informed (heuristic) search algorithm is one that uses heuristics to guide the search process, making it more efficient than uninformed search algorithms. One common example of an informed search algorithm is the A (A-star) search algorithm*.

The A* algorithm combines features of Dijkstra's algorithm (which is an uninformed search) and greedy best-first search (which is an informed search). It uses a heuristic to estimate the cost from the current node to the goal and adds this to the cost taken to reach the current node from the start. The formula utilized by A* can be represented as:

$f(n) = g(n) + h(n)$

where:

• $f(n)$ is the total estimated cost of the cheapest solution through node $n$,
• $g(n)$ is the cost from the start node to node $n$,
• $h(n)$ is the estimated cost (heuristic) from node $n$ to the goal.

The efficiency of A* comes from its use of the heuristic function, which can dramatically reduce the search space compared to a blind search. Other examples of informed search algorithms include Greedy Best-First Search and Hill Climbing Search.