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python/графы/дейкстра.py

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+graph = {
+	1: {
+		2: 7,
+		3: 9,
+		6: 14
+	},
+	2: {
+		1: 7,
+		3: 10,
+		4: 15
+	},
+	3: {
+		1: 9,
+		2: 10,
+		4: 11,
+		6: 2
+	},
+	4: {
+		2: 15,
+		3: 11,
+		5: 6,
+	},
+	5: {
+		4: 6,
+		6: 9,
+	},
+	6: {
+		1: 14,
+		5: 9,
+		3: 2
+	}
+}
+
+
+class GraphPoint:
+	def __init__(self, graph, number, routes):
+		self.graph = graph
+		self.number = number
+		self.routes = routes
+		self.visited = False
+		self.minimum_range = 9999
+
+
+	def get_unvisited_neighbours(self):
+		neighbours = []
+		for number in self.routes.keys():
+			point = self.graph.get_point(number)
+			if not point.visited:
+				neighbours.append(point)
+		return neighbours
+
+
+	def get_range(self, point):
+		return self.routes[point.number]
+
+
+	def get_all_neighbours(self):
+		neighbours = [self.graph.get_point(x) for x in self.routes.keys()]
+		return neighbours
+
+
+
+class Graph:
+	def __init__(self, data):
+		self.data = data
+		self.points = {}
+
+		for number, routes in data.items():
+			self.points[number] = GraphPoint(self, number, routes)
+
+		self.points[1].minimum_range = 0
+
+
+	def get_point(self, number):
+		point = self.points.get(number)
+
+		if point is None:
+			raise ValueError(f"Graph has no point with number {number}")
+
+		return point
+
+
+
+myGraph = Graph(graph)
+
+
+start = myGraph.get_point(1)
+queue = []
+queue.append(start)
+
+
+while len(queue) > 0:
+	current_point = min(queue, key=lambda x: x.minimum_range)
+	queue.remove(current_point)
+	current_point.visited = True
+
+	for neighbour in current_point.get_unvisited_neighbours():
+		new_range = current_point.minimum_range + current_point.get_range(neighbour)
+
+		if new_range < neighbour.minimum_range:
+			neighbour.minimum_range = new_range
+
+		queue.append(neighbour)
+
+
+
+path = []
+pos = myGraph.get_point(5)
+
+
+while pos != start:
+	for neighbour in pos.get_all_neighbours():
+		if neighbour.get_range(pos) + neighbour.minimum_range == pos.minimum_range:
+			path.append(pos)
+			pos = neighbour
+			break
+
+path.append(start)
+
+for i in path[::-1]:
+	print(i.number)
+# No comments here. Good l_ck!