算法之LCS

1. packagecom.eshore.sweetop.dynamicprogramming;
3. publicclassLCS{
4. publicstaticvoidLCSLength(char[]x,char[]y){
5. intm=x.length;
6. intn=y.length;
7. int[][]c=newint[m+1][n+1];
8. char[][]b=newchar[m+1][n+1];
10. for(inti=1;i<=m;i++){
11. c[i][0]=0;
12. }
13. for(inti=1;i<n;i++){
14. c[0][i]=0;
15. }
16. for(inti=1;i<=m;i++){
17. for(intj=1;j<=n;j++){
18. if(x[i-1]==y[j-1]){
19. c[i][j]=c[i-1][j-1]+1;
20. b[i][j]='※';
21. }elseif(c[i-1][j]>=c[i][j-1]){
22. c[i][j]=c[i-1][j];
23. b[i][j]='↑';
24. }else{
25. c[i][j]=c[i][j-1];
26. b[i][j]='←';
27. }
28. }
29. }
30. display(b,x,m,n);
31. }
33. publicstaticvoiddisplay(char[][]b,char[]x,inti,intj){
34. if(i==0||j==0){
35. return;
36. }
37. if(b[i][j]=='※'){
38. display(b,x,i-1,j-1);
39. System.out.print(x[i-1]);
40. }elseif(b[i][j]=='↑'){
41. display(b,x,i-1,j);
42. }else{
43. display(b,x,i,j-1);
44. }
45. }
47. publicstaticvoidmain(String[]args){
48. char[]a={'A','B','C','B','D','A','B'};
49. char[]b={'B','D','C','A','B','A'};
50. LCS.LCSLength(a,b);
51. System.out.println();
52. LCS.LCSLength(b,a);
53. }
54. }