2524 1611 并查集

http://acm.pku.edu.cn/JudgeOnline/problem?id=2524

http://acm.pku.edu.cn/JudgeOnline/problem?id=1611

code 2524

1. #include<iostream>
2. usingnamespacestd;
4. intpre[50010],num;
6. intfind(inta);
7. voidun(inta,intb);
8. intmain()
9. {
10. intn,m;
11. inti,a,b,T(1);
12. freopen("in.txt","r",stdin);
13. while(cin>>n>>m&&n&&m)
14. {
15. num=n;//初始化是每个人的信仰都不同
17. for(i=1;i<=50005;i++)
18. pre[i]=0;
19. for(i=1;i<=m;i++)
20. {
21. scanf("%d%d",&a,&b);
22. un(a,b);
23. }
26. cout<<"Case"<<T++<<":"<<num<<endl;
27. }
30. return0;
31. }
33. intfind(inta)//路径压缩
34. {
35. intt=a,z;
36. while(pre[t]!=0)t=pre[t];
37. while(a!=t)
38. {
39. z=pre[a];
40. pre[a]=t;
41. a=z;
42. }
43. returnt;
44. }
46. voidun(inta,intb)
47. {
48. //intaa,bb;
49. intaa,bb;
50. aa=find(a);
51. bb=find(b);
52. if(aa==bb&&aa)//祖先一样的情况
53. return;
54. if(aa==0)
55. pre[bb]=aa;
56. else
57. pre[aa]=bb;
58. num--;
60. }

code 1611

1. #include<iostream>
2. #include<algorithm>
4. usingnamespacestd;
6. shortpre[30001],num[30001];
7. voidun(inta,intb);
8. intfind(inta);
9. intmain()
10. {
11. intn,i,m,a,j,b,temp;
14. freopen("in.txt","r",stdin);
15. while(cin>>n>>m&&m||n)
16. {
17. for(i=0;i<30001;i++)
18. pre[i]=i;
19. for(i=0;i<m;i++)
20. {
21. cin>>a;
22. for(j=0;j<a;j++)
23. {
24. cin>>b;
25. if(j==0)
26. temp=b;
29. un(temp,b);
30. }
31. }
32. for(i=0;i<30001;i++)
33. find(i);
34. sort(pre,pre+30001);
35. n=0,j=0;
36. while(!pre[n++])j++;
37. cout<<j<<endl;
38. }
42. return0;
44. }
45. intfind(inta)//未用路径压缩
46. {
47. intt;
48. t=a;
49. while(pre[t]!=t)t=pre[t];
50. pre[a]=t;
51. returnt;
52. }
53. voidun(inta,intb)
54. {
55. intaa,bb;
56. aa=find(a);
57. bb=find(b);
58. if(aa==0)
59. pre[bb]=aa;
60. else
61. pre[aa]=bb;
62. }