Kruskal算法求最小生成樹java

1、Kruskal 算法求最小生成樹(JAVA)代碼：packagehomework;importjava.util.Scanner;importjava.util.Arrays;importjava.util.ArrayList;classEdgepublicintstart;/始邊publicintend;/終邊publicdoublecost;/版重publicclassMinSpanningTree_KruskalprivatestaticintMAX=100;privateArrayListedge=newArrayList();/整個圖的邊privateArrayListtarget=

2、newArrayList();/目標(biāo)邊，最小生成樹privateintparent=newintMAX;/標(biāo)志所在的集合privatestaticdoubleINFINITY=99999999.99;/定義無窮大privatedoublemincost=0.0;/服小成本privateintn;/結(jié)點(diǎn)個數(shù)publicMinSpanningTree_Kruskal()publicstaticvoidmain(Stringargs)MinSpanningTree_Kruskalsp=newMinSpanningTree_Kruskal();sp.init();sp.kruskal();sp.pri

3、nt();初始化publicvoidinit()Scannerscan=newScanner(System.in);intp,q;doublew;System.out.println(請輸入結(jié)點(diǎn)個數(shù)：);n=scan.nextInt();System.out.println(”請輸入各條邊及權(quán)值(每次輸入一組數(shù)據(jù)按回車確認(rèn)，+”最后輸入-1-1-1 結(jié)束輸入過程);while(true)p=scan.nextInt();q=scan.nextInt();w=scan.nextDouble();if(p0|q0|w0)break;)Edgee=newEdge();e.start=p;e.end=

4、q;e.cost=w;edge.add(e);)mincost=0.0;for(inti=1;i=n;+i)parenti=i;)集合合并publicvoidunion(intj,intk)for(inti=1;i=n;+i)if(parenti=j)parenti=k;/prim 算法主體publicvoidkruskal()/找剩下的 n-2 條邊inti=0;while(i0)/每次取一最小邊，并刪除doublemin=INFINITY;inttag=0;Edgetmp=null;for(intj=0;jedge.size();+j)Edgett=edge.get(j);if(tt.co

5、stmin)min=tt.cost;tmp=tt;intjj=parenttmp.start;intkk=parenttmp.end;/去掉環(huán)if(jj!=kk)+i;target.add(tmp);mincost+=tmp.cost;union(jj,kk);edge.remove(tmp);)if(i!=n-1)System.out.println(沒有最小生成樹)；System.exit(0);)打印結(jié)果publicvoidprint()doublesum=0;System.out.println(最小生成樹：);for(inti=0;itarget.size();+i)Edgee=target.get(i);System.out.println(第+(i+1)+條邊：+e.start+-+e.end+權(quán)值：+e.cost);sum=sum+e.cost;System.out.println(最小生成樹的權(quán)值:+sum);調(diào)試結(jié)果:IIIIIMiIMII-tlljlIIIrHJSMi-rCU.hF|19-HMSUTBIJ竄II111IC-l-r4IXXIXXk,4TUII串T.H41.F|l-T.請輸入結(jié)點(diǎn)個數(shù)：一一請輸入各條邊及權(quán)值(每袂輸入一