算法之动态规划最优二叉树

1. packagecom.eshore.sweetop.dynamicprogramming;
3. publicclassBestBinTree{
4. //关键字节点,p[0]为构造数据
5. //double[]p={0,0.15,0.10,0.05,0.10,0.20};
6. //虚拟节点
7. //double[]q={0.05,0.10,0.05,0.05,0.05,0.10};
8. //规模
9. //intn=5;
11. double[]p={0,0.04,0.06,0.08,0.02,0.10,0.12,0.14};
12. double[]q={0.06,0.06,0.06,0.06,0.05,0.05,0.05,0.05};
13. staticintn=7;
15. double[][]e=newdouble[n+2][n+1];
16. double[][]w=newdouble[n+2][n+1];
17. int[][]root=newint[n+2][n+2];
19. publicvoidoptimalBest(){
20. for(inti=1;i<e.length;i++){
21. e[i][i-1]=q[i-1];
22. w[i][i-1]=q[i-1];
23. }
26. for(intl=1;l<n+1;l++){
27. for(inti=1;i<=n-l+1;i++){
28. intj=i+l-1;
29. e[i][j]=Double.MAX_VALUE;
30. w[i][j]=w[i][j-1]+p[j]+q[j];
31. for(intr=i;r<=j;r++){
32. doublet=e[i][r-1]+e[r+1][j]+w[i][j];
33. if(t<e[i][j]){
34. e[i][j]=t;
35. System.out.println(r);
36. root[i][j]=r;
37. }
38. }
39. }
40. }
41. //BestBinTree.display(w);
42. //BestBinTree.display(e);
43. BestBinTree.display(root);
45. BestBinTree.viewTree(root);
46. }
48. publicstaticvoiddisplay(double[][]a){
49. for(inti=1;i<a.length;i++){
50. for(intj=1;j<a[0].length;j++){
51. System.out.print(String.format("%.2f",a[i][j])+"/t");
52. }
53. System.out.println();
54. }
55. }
57. publicstaticvoiddisplay(int[][]a){
58. for(inti=1;i<a.length;i++){
59. for(intj=1;j<a[0].length;j++){
60. if(i<=j)
61. System.out.print(a[i][j]+"");
62. }
63. System.out.println();
64. }
65. }
67. publicstaticvoidviewTree(int[][]a){
68. System.out.println("根是k"+a[1][n]);
69. view(a,a[1][n],1,n);
70. //System.out.println(a[6][7]);
71. }
73. publicstaticvoidview(int[][]a,introot,inti,intj){
74. if(a[i][root-1]==0){
75. System.out.println("k"+root+"左孩子是d"+(root-1));
76. }else{
77. System.out.println("k"+root+"左孩子是k"+a[i][root-1]);
78. view(a,a[i][root-1],i,root-1);
79. }
80. if(a[root+1][j]==0){
81. System.out.println("k"+root+"右孩子是d"+root);
82. }else{
83. System.out.println("k"+root+"右孩子是k"+a[root+1][j]);
84. view(a,a[root+1][j],root+1,j);
85. }
86. }
89. publicstaticvoidmain(String[]args){
90. BestBinTreebbt=newBestBinTree();
91. bbt.optimalBest();
92. }
94. }