Problem 1 (20%): Label-setting (Dijkstra's ) algorithm for seeking the shortest 12.6 3.3 7.2 5.0 4 4.8 8.4 2.2 5.0 4.3 Please find the shortest path from node 4 to node 2. All the links in the above figure is bi- directional You need to use a doublet (a, b) on each nodes to describe the intermediate process. "a" is the latest predecessor for tracing back the path later and b is the latest label value. Please refer to the second in-class example of the shortest path algorithms. (10%) a. b. After you find the shortest path from node 4 to node 2, please also specify the length of shortest paths from node 4 to node 1,3,5,6. (10%)