C++ graphs & binary search trees

Jack bought a new car, and he wants to travel to visit his friends, but he has too many. At each intersection he has a friend, so he must find the shortest possible way not to spend too much time on the road. Each street is a one-way street. The intersections are uniquely numbered from 1 to n, with n < 50. The streets also contain numbers, which represent the distances between 2 intersections. As Jack spent all his money for the new car, he has no money left to buy a GPS. Help Jack find the shortest path to his friends. If there is no path available, display an appropriate message. Hint: Consider a graph in which the vertices are intersections, and the arcs are the streets determined by the intersections. Tasks: (1p) a) Modify the "Graph" class to represent an oriented graph. (4p) b) Read from the keyboard the "streets" and the distances between 2 intersections. Save them in a graph. Subject 2 – BST [5p] (0.5p) a) Read letters from the keyboard and insert them in a BST. The reading process stops when the user inserts the character 0 (zero). (0.75p) b) Find the common ancestor of 2 given nodes. (0.75p) c) Write a function to check is a node is a grandparent of a given node. (1p) d) Design an algorithm which creates a linked list of all the nodes at each depth (i.e., if the tree has depth D, you’ll have D linked lists). (1p) e) Check if a BST is perfect or not (all leaves are at the same distance from the root). (1p) f) Perform a right rotation of the BST.