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			60 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			Kotlin
		
	
	
	
	
	
			
		
		
	
	
			60 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			Kotlin
		
	
	
	
	
	
/**
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 * File: graph_dfs.kt
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 * Created Time: 2024-01-25
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 * Author: curtishd (1023632660@qq.com)
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 */
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package chapter_graph
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import utils.Vertex
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/* 深度优先遍历辅助函数 */
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fun dfs(
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    graph: GraphAdjList,
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    visited: MutableSet<Vertex?>,
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    res: MutableList<Vertex?>,
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    vet: Vertex?
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) {
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    res.add(vet)     // 记录访问顶点
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    visited.add(vet) // 标记该顶点已被访问
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    // 遍历该顶点的所有邻接顶点
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    for (adjVet in graph.adjList[vet]!!) {
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        if (visited.contains(adjVet))
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            continue  // 跳过已被访问的顶点
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        // 递归访问邻接顶点
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        dfs(graph, visited, res, adjVet)
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    }
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}
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/* 深度优先遍历 */
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// 使用邻接表来表示图,以便获取指定顶点的所有邻接顶点
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fun graphDFS(graph: GraphAdjList, startVet: Vertex?): MutableList<Vertex?> {
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    // 顶点遍历序列
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    val res = mutableListOf<Vertex?>()
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    // 哈希集合,用于记录已被访问过的顶点
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    val visited = HashSet<Vertex?>()
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    dfs(graph, visited, res, startVet)
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    return res
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}
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/* Driver Code */
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fun main() {
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    /* 初始化无向图 */
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    val v = Vertex.valsToVets(intArrayOf(0, 1, 2, 3, 4, 5, 6))
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    val edges = arrayOf(
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        arrayOf(v[0], v[1]),
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        arrayOf(v[0], v[3]),
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        arrayOf(v[1], v[2]),
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        arrayOf(v[2], v[5]),
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        arrayOf(v[4], v[5]),
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        arrayOf(v[5], v[6])
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    )
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    val graph = GraphAdjList(edges)
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    println("\n初始化后,图为")
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    graph.print()
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    /* 深度优先遍历 */
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    val res = graphDFS(graph, v[0])
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    println("\n深度优先遍历(DFS)顶点序列为")
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    println(Vertex.vetsToVals(res))
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} |