Just adding a question to keep Github updated

Author: kunalarya873

Trees&Graphs(Questions)/BuildOrder2.py

@@ -0,0 +1,46 @@
+def create_graph(projects, dependencies):
+   project_graph = {}
+   for project in projects:
+       project_graph[project] = []
+   for pairs in dependencies:
+       project_graph[pairs[0]].extend(pairs[1])
+   return project_graph
+graph = create_graph(['A', 'B', 'C', 'D', 'E', 'F'], [('A','D'), ('F', 'B'), ('B','D'), ('F','A'), ('D','C')])
+# print(graph)
+ 
+def get_projects_with_dependencies(graph):
+   projects_with_depen = set()
+   for project in graph:
+       # addin values from dictionaty because values are dependednt of key
+       projects_with_depen = projects_with_depen.union(set(graph[project]))
+   
+   return projects_with_depen
+ 
+dependents = get_projects_with_dependencies(graph)
+# print(dependents)
+ 
+def get_projects_wo_dependencies(projects_with, graph):
+   projects_wo_dependencies = set()
+   for project in graph:
+       if not project in projects_with:
+           projects_wo_dependencies.add(project)
+   return projects_wo_dependencies
+notDependents = get_projects_wo_dependencies(dependents, graph)
+# print(notDependents)
+ 
+def find_build_order(projects, dependencies):
+   build_order = []
+   project_graph = create_graph(projects, dependencies)
+   while project_graph:
+       print(project_graph)
+       projects_with_depen = get_projects_with_dependencies(project_graph)
+       projects_wo_depen = get_projects_wo_dependencies(projects_with_depen, project_graph)
+       print(projects_wo_depen)
+       if len(projects_wo_depen) == 0 and project_graph:
+           raise ValueError('There is a cycle in the build order')
+       for independent_project in projects_wo_depen:
+           build_order.append(independent_project)
+           del project_graph[independent_project]
+   return build_order
+ 
+print(find_build_order(['A', 'B', 'C', 'D', 'E', 'F'], [('A','D'), ('F', 'B'), ('B','D'), ('F','A'), ('D','C')]))