poj2492

http://poj.org/problem?id=2492

跟1703一样 两种状态 并查集+偏移量

两只虫子发射架关系 判断有没有虫子是同性恋 两两合并 在一棵树上找右没有两个节点跟跟节点的关系（只有0,1两种）是相同的，相同就是gay

注意一点 两组数据间有空行 

View Code

 1 #include <stdio.h>

 2 #include <stdlib.h>

 3 int father[2001],num[2001],r[2001];

 4 int find(int x)

 5 {

 6     if(x!=father[x])

 7     {

 8         int y = father[x];

 9         father[x] = find(father[x]);

10         num[x] = (num[x]+num[y])%2;

11     }

12     return father[x];

13 }

14 void union1(int x, int y)

15 {

16     int x1 = find(x);

17     int y1 = find(y);

18     if(x1!=y1)

19     {

20         if(r[x1]>r[y1])

21         {

22             father[y1] = x1;

23             num[y1] = (num[x]-num[y]+1)%2;

24         }

25         else

26         {

27             father[x1] = y1;

28             num[x1] = (num[y]-num[x]+1)%2;

29             if(r[x1] == r[y1])

30             r[y1]++;

31         }

32     }

33 }

34 int main()

35 {

36     int i, j, m, n,t,a,b,g;

37     long k;

38     scanf("%d", &t);

39     while(t--)

40     {

41         k++;

42         scanf("%d%d", &n, &m);

43         int flag = 0;

44         for(i = 1 ; i <= n ; i++)

45         {

46             father[i] = i;

47             r[i] = 0;

48             num[i] = 0;

49         }

50         j = 0;

51         for(i = 1 ; i <= m ; i++)

52         {

53             scanf("%d%d", &a,&b);

54             if(a!=b)

55             union1(a,b);

56             if(find(a) == find(b)&&num[a]==num[b])

57             flag = 1;

58         }

59         printf("Scenario #%ld:\n",k);

60         if(flag == 0)

61         printf("No suspicious bugs found!\n");

62         else

63         printf("Suspicious bugs found!\n");

64         if(t!=0)

65         printf("\n");

66     }

67     return 0;

68 }