Uniform-cost search
When actions have different costs, an obvious choice is to use best-first search where the evaluation function is the cost of the path from the root to the current node.
Complexity
The complexity of uniform-cost search is characterized in terms of the cost of the
optimal solution $C*C^*$, and $\epsilon$, a lower bound on the cost of each action, with $\epsilon$ > 0. Then the
algorithm’s worst-case time and space complexity is
$$O(b^{1+[\frac{C^*}{\epsilon}]})$$
TO CONTINUE