用了都说好的Python、Java双实现的Graph图数据结构的定义

'''
一个好用的Graph的定义
权重，from Node到to Node
【
 weight,from ,to
[12,    2,    4];
[4,    2,    7]
....
】
好的定义已经帮你解决了很多问题，比如这个图的Node出度入度直接就可以求


python代码的图定义是我直接从下面的Java代码翻译过来的
'''

class Graph:
    def __init__(self):
        self.nodes={
    
    }
        self.edges=set()
class Node:
    def __init__(self,valuse):
        self.valuse=valuse
        self.In=0 #入度
        self.out=0#出度
        self.nexts=[]
        self.edges=[]
class Edge:
    def __init__(self,weight,From,to):
        self.weight=weight
        self.From=From
        self.to=to

def createGraph(matrix):
    graph=Graph()
    for i in range(len(matrix)):
        weight=matrix[i][0]
        From=matrix[i][1]
        to=matrix[i][2]
        if(From not in graph.nodes):
            graph.nodes.update({
    
    From:Node(From)})
        if (to not in graph.nodes):
            graph.nodes.update({
    
    to:Node(to)})
        fromNode=graph.nodes.get(From)
        toNode=graph.nodes.get(to)
        newEdge=Edge(weight,fromNode,toNode)
        fromNode.nexts.append(toNode)
        fromNode.out+=1
        fromNode.In+=1
        fromNode.edges.append(newEdge)
        graph.edges.add(newEdge)
    return graph
if __name__ == '__main__':
    matrix=[[1,2,3],[4,5,6]]
    graph=createGraph(matrix)
    print(graph.nodes.keys())
'''
##  Java注释  有类型 看着方便
public class Graph {
	public HashMap<Integer,Node> nodes;
	public HashSet<Edge> edges;

	public Graph() {
		nodes = new HashMap<>();
		edges = new HashSet<>();
	}
}

public class Node {
	public int value;
	public int in;
	public int out;
	public ArrayList<Node> nexts;
	public ArrayList<Edge> edges;

	public Node(int value) {
		this.value = value;
		in = 0;
		out = 0;
		nexts = new ArrayList<>();
		edges = new ArrayList<>();
	}
}


public class Edge {
	public int weight;
	public Node from;
	public Node to;

	public Edge(int weight, Node from, Node to) {
		this.weight = weight;
		this.from = from;
		this.to = to;
	}

}

	public static Graph createGraph(Integer[][] matrix) {
		Graph graph = new Graph();
		for (int i = 0; i < matrix.length; i++) {
			Integer weight = matrix[i][0];
			Integer from = matrix[i][1];
			Integer to = matrix[i][2];
			if (!graph.nodes.containsKey(from)) {
				graph.nodes.put(from, new Node(from));
			}
			if (!graph.nodes.containsKey(to)) {
				graph.nodes.put(to, new Node(to));
			}
			Node fromNode = graph.nodes.get(from);
			Node toNode = graph.nodes.get(to);
			Edge newEdge = new Edge(weight, fromNode, toNode);
			fromNode.nexts.add(toNode);
			fromNode.out++;
			toNode.in++;
			fromNode.edges.add(newEdge);
			graph.edges.add(newEdge);
		}
		return graph;
	}

'''