poj2513Colored Sticks(无向图判欧拉路、回路+trie树）

http://poj.org/problem?id=2513

每个单词为一个节点 并查集判联通 度数为偶数或有两个为奇数 4A 第三次是由于有多余的测试输出没删掉 前两次统计多少个单词 统计错了

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 1 #include <iostream>

 2 #include<cstdio>

 3 #include<string.h>

 4 using namespace std;

 5 char s[500011][11];

 6 int dd,father[500011],r[500011],dk[500011];

 7 struct node

 8 {

 9     int de,da;

10     node *next[27];

11     node()

12     {

13         de = 0;

14         da = 0;

15         memset(next,0,sizeof(next));

16     }

17 };

18 int find(int x)

19 {

20     if(x!=father[x])

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

22     return father[x];

23 }

24 void ctree(node *t,char *c,int j)

25 {

26     int i,d,k = strlen(c);

27     node *p = t;

28     for(i = 0 ; i < k ; i++)

29     {

30         d = c[i]-'a';

31         if(p->next[d]==NULL)

32         p->next[d] = new node;

33         p = p->next[d];

34     }

35     p->de++;

36     if(p->da==0)

37     {

38         dd++;

39         p->da = dd;

40     }

41     r[j] = p->da;

42     dk[p->da] = p->de;

43 }

44 int main()

45 {

46     int i = 0,j,k,n,m;

47     dd = 0;

48     node *t = new node;

49     for(j = 1; j <= 500010 ; j++)

50     father[j] = j;

51     while(scanf("%s %s",s[i],s[i+1])!=EOF)

52     {

53         /*if(s[i][0]=='#')

54         break;*/

55         ctree(t,s[i],i);

56         ctree(t,s[i+1],i+1);

57         int px = find(r[i]);

58         int py = find(r[i+1]);

59         if(px!=py)

60         father[px] = py;

61         i+=2;

62     }

63     int num = 0;

64     for(j = 1 ;j <= dd ; j++)

65     if(father[j]==j)

66     {

67         num++;

68         if(num>1)

69         break;

70     }

71     if(num>1)

72     printf("Impossible\n");

73     else

74     {

75         num = 0;

76         for(j = 1 ; j <= dd ; j++)

77         {

78             if(dk[j]%2!=0)

79             num++;

80         }

81         if(num==2||num == 0)

82         printf("Possible\n");

83         else

84         printf("Impossible\n");

85     }

86     return 0;

87 }