[mypy] Type annotations for graphs/finding_bridges.py and graphs/random_graph_generator.py (#5795)

* [mypy] Annotate `graphs/finding_bridges.py`

* Remove from excluded in `mypy.ini`

* Add doctest.testmod()

* psf/black formatting

* Annotations for `graphs/random_graph_generator.py`

* Remove from excluded in `mypy.ini`

* Resolve merge conflict

* Resolve merge conflict

* Update mypy.ini

* Update mypy.ini

* Remove from excluded

Author: Rohanrbharadwaj

Diff for: graphs/finding_bridges.py

@@ -93,8 +93,14 @@ def dfs(at, parent, bridges, id):
                 # This edge is a back edge and cannot be a bridge
                 low[at] = min(low[at], low[to])
 
-    bridges = []
+    bridges: list[tuple[int, int]] = []
     for i in range(n):
         if not visited[i]:
             dfs(i, -1, bridges, id)
     return bridges
+
+
+if __name__ == "__main__":
+    import doctest
+
+    doctest.testmod()

Diff for: graphs/random_graph_generator.py

@@ -26,7 +26,7 @@ def random_graph(
     >>> random_graph(4, 0.5, True)
     {0: [1], 1: [2, 3], 2: [3], 3: []}
     """
-    graph = {i: [] for i in range(vertices_number)}
+    graph: dict = {i: [] for i in range(vertices_number)}
 
     # if probability is greater or equal than 1, then generate a complete graph
     if probability >= 1:

Diff for: mypy.ini

@@ -2,4 +2,4 @@
 ignore_missing_imports = True
 install_types = True
 non_interactive = True
-exclude = (graphs/breadth_first_search.py|graphs/breadth_first_search_2.py|graphs/check_cycle.py|graphs/finding_bridges.py|graphs/greedy_min_vertex_cover.py|graphs/random_graph_generator.py|matrix_operation.py|other/least_recently_used.py|other/lfu_cache.py|other/lru_cache.py|searches/simulated_annealing.py|searches/ternary_search.py)
+exclude = (graphs/breadth_first_search.py|graphs/breadth_first_search_2.py|graphs/check_cycle.py|graphs/greedy_min_vertex_cover.py|matrix_operation.py|other/least_recently_used.py|other/lfu_cache.py|other/lru_cache.py|searches/simulated_annealing.py|searches/ternary_search.py)