竞赛2-s图论专题3最短路问题

TobePDFcreatedwithpdfFactoryProtrialversion 三、最短路算PDFcreatedwithpdfFactoryProtrialversion

例已知如例已知如下图所示的单行线交通网，每弧1要从v1出发，通过这个交通网到去。求使总费用最小的旅行路 22 PDFcreatedwithpdfFactoryProtrialversion 一、最短路问P0，

w(0PPDFcreatedwithpdfFactoryProtrialversion 用P，T分别表示某个顶点的P标号和T标号Si表示第i步时,具有P*λ(v)=m表示在从vs到v的最短 λ(v)=M表示D中不含从vs到v的路λ(v)0表示PDFcreatedwithpdfFactoryProtrialversion 2、最短路算法(Dijkstra算法每一个v≠vs,令T(v)=+∞,λ(v)=M;k=s(当前点（１）判断：如果Si=V,算法终止。此时,对每v∈Si，d(vs,v)=P(v)；否则转入 (vkvjA且vjSi的点vj如果T(vj)>P(vk)+wkjT(vj)P(vk)wkj,(vj)否则转入PDFcreatedwithpdfFactoryProtrialversion TTji)min{T(vvjj如果T(vji)<+∞,则把vji的T标号变为PiiSi1转入

},kj,iivSi,d(vs,v)T注意、Dijkstra算法同样适用于无向、DijkstraPDFcreatedwithpdfFactoryProtrialversion 最短路算法(Dijkstra算法PDFcreatedwithpdfFactoryProtrialversion ．现 要从v1出发，通过这个交通网

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v8最短路262664 PDFcreatedwithpdfFactoryProtrialversion clearallV=[00;11;10;1-1;21;20;21;330;3-1;4E=[125;135;145;232;32;25262;365;372;473;567585;682;693;792;73;899102;8115;9114;1011PDFcreatedwithpdfFactoryProtrialversion [dSP,sp]=grShortPath(E,s,t);%thematrixofshortestgrPlot(V(:,1:2),[sp(1:end-PDFcreatedwithpdfFactoryProtrialversion 中国邮递员问图论描述给定一个赋权的连通图,求最 回路 （Euler）行迹＊ 行迹称 回路＊ 回路的图称 图PDFcreatedwithpdfFactoryProtrialversion 连通图G上邮递员问题的算法(Fleury算法、求出G’的Euler闭迹C,则C就是G的最优邮路.结束PDFcreatedwit