 Hello everyone, this is Alice Gao. In this video, I'm going to trace greedy best-first search on a search graph. Recall that greedy BFS chooses to remove the path with the lowest heuristic value from the frontier at each step. I will use the same type written rule as before. Order the path by their last notes and choose the path that comes first in alphabetical order. During this process, I will keep track of a few things. The frontier, the heuristic value for each path in the frontier and the search tree. I will label the nodes in the order of expansion. First, let's add the initial state s to the frontier and to the search tree. Next, remove s from the frontier. As is not the goal, let's expand it. s has two successors, b and c. Add sb with a heuristic value of 7 and sc with a heuristic value of 3 to the frontier. The path with the smallest heuristic value is sc. Let's remove sc from the frontier. c is not the goal, let's expand it. c has one successor h. Let's add sch with a heuristic value of 100 to the frontier. Next, sb has the lowest heuristic value of 7. Let's remove sb from the frontier. b is not the goal, let's expand it. b has three successors, c, d and e. Let's add sbc, sbd and sb e to the frontier with their heuristic values 3, 1 and 4. sbd has the lowest heuristic value of 1. Let's remove sbd from the frontier. d is not the goal, let's expand it. d has two successors, f and g. Let's add sbdf and sbdg to the frontier with their heuristic values 6 and 0. sbdg has the lowest heuristic value of 0. Let's remove sbdg from the frontier. g is the goal, let's return the solution sbdg. This completes the tracing process. As you can see, greedy bfs guides the search by only using the heuristic value. It doesn't look at any other information. That's everything for this example on tracing greedy best for search. Thank you very much for watching. I will see you in the next video. Bye for now.