$2$ Dijkstra $(20$ pts$)$

Execute Dijkstra's algorithm on the weighted graph below, starting from the source node s at the bottom. Anotate the nodes with their $($incrementally imrpoving$)$ distance$-$from$-$s upper$-$bound, taking care to write these values smally and neatly. Whenever you update a node with a new, immproved distance bound, don't erase it or scribble it out but neatly draw a line through it and write the new distacne next to it$,$ maintaining at least a semi$-$visiivle record of the scries of imporvements the node went through over the course of the algorithm. SImilarly, until a node is finalized $("$closed$"),$ draw its parent back$-$edge arrows neatly and faintly so that you'll be able to neatly draw a line through them when they are superceded. Finally, each time you finalize a node, draw a dark circle around it$,$ and make its parent back$-$edge arrow bold as in class.

$3$