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Resolved issues regarding ruff testing and merge conflicts

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This commit is contained in:
Joelkurien 2024-10-26 03:10:30 +11:00
commit 346a955946
2 changed files with 24 additions and 23 deletions
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1
DIRECTORY.md
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@ -503,6 +503,7 @@
* [Graphs Floyd Warshall](graphs/graphs_floyd_warshall.py) * [Graphs Floyd Warshall](graphs/graphs_floyd_warshall.py)
* [Greedy Best First](graphs/greedy_best_first.py) * [Greedy Best First](graphs/greedy_best_first.py)
* [Greedy Min Vertex Cover](graphs/greedy_min_vertex_cover.py) * [Greedy Min Vertex Cover](graphs/greedy_min_vertex_cover.py)
* [Johnson Graph](graphs/johnson_graph.py)
* [Kahns Algorithm Long](graphs/kahns_algorithm_long.py) * [Kahns Algorithm Long](graphs/kahns_algorithm_long.py)
* [Kahns Algorithm Topo](graphs/kahns_algorithm_topo.py) * [Kahns Algorithm Topo](graphs/kahns_algorithm_topo.py)
* [Karger](graphs/karger.py) * [Karger](graphs/karger.py)

22
graphs/johnson_graph.py
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@ -9,16 +9,16 @@ class JohnsonGraph:
self.edges = [] self.edges = []
self.graph = {} self.graph = {}
#add vertices for a graph # add vertices for a graph
def add_vertices(self, u): def add_vertices(self, u):
self.graph[u] = [] self.graph[u] = []
#assign weights for each edges formed of the directed graph # assign weights for each edges formed of the directed graph
def add_edge(self, u, v, w): def add_edge(self, u, v, w):
self.edges.append((u, v, w)) self.edges.append((u, v, w))
self.graph[u].append((v,w)) self.graph[u].append((v, w))
#perform a dijkstra algorithm on a directed graph # perform a dijkstra algorithm on a directed graph
def dijkstra(self, s): def dijkstra(self, s):
distances = {vertex: sys.maxsize-1 for vertex in self.graph} distances = {vertex: sys.maxsize-1 for vertex in self.graph}
pq = [(0,s)] pq = [(0,s)]
@ -31,8 +31,8 @@ class JohnsonGraph:
continue continue
for node, w in self.graph[v]: for node, w in self.graph[v]:
if distances[v]+w < distances[node]: if distances[v] + w < distances[node]:
distances[node] = distances[v]+w distances[node] = distances[v] + w
heapq.heappush(pq, (distances[node], node)) heapq.heappush(pq, (distances[node], node))
return distances return distances
@ -43,8 +43,8 @@ class JohnsonGraph:
for u in self.graph: for u in self.graph:
for u, v, w in self.edges: for u, v, w in self.edges:
if distances[u] != sys.maxsize-1 and distances[u]+w<distances[v]: if distances[u] != sys.maxsize - 1 and distances[u] + w < distances[v]:
distances[v] = distances[u]+w distances[v] = distances[u] + w
return distances return distances
@ -52,7 +52,6 @@ class JohnsonGraph:
# could not be handled by either the dijkstra # could not be handled by either the dijkstra
#or the bellman ford algorithm efficiently #or the bellman ford algorithm efficiently
def johnson_algo(self): def johnson_algo(self):
self.add_vertices("#") self.add_vertices("#")
for v in self.graph: for v in self.graph:
if v != "#": if v != "#":
@ -74,13 +73,14 @@ class JohnsonGraph:
for u in self.graph: for u in self.graph:
new_dist = self.dijkstra(u) new_dist = self.dijkstra(u)
for v in self.graph: for v in self.graph:
if new_dist[v] < sys.maxsize-1: if new_dist[v] < sys.maxsize - 1:
new_dist[v] += n[v] - n[u] new_dist[v] += n[v] - n[u]
distances.append(new_dist) distances.append(new_dist)
return distances return distances
g = JohnsonGraph() g = JohnsonGraph()
#this a complete connected graph # this a complete connected graph
g.add_vertices("A") g.add_vertices("A")
g.add_vertices("B") g.add_vertices("B")
g.add_vertices("C") g.add_vertices("C")