HDU1198

这道题DFS,BFS,并查集好像都可以

觉得深搜跟并查集可能会更简单一些

 1 #include "iostream"

 2 #include "algorithm"

 3 #include "memory.h"

 4 #include "cmath"

 5 #include "string"

 6 using namespace std;

 7 #define MAXN 550

 8 

 9 

10 char s[15][6] = {

11     { "1100" }, {"0110"}, {"1001"}, {"0011"}, {"0101"}, {"1010"}, {"1110"}, {"1101"}, {"1011"}, {"0111"}, {"1111"}

12 };

13 int n, m,num;

14 int fa[MAXN*MAXN];

15 string a[550];

16 

17 int find(int x)

18 {

19     if (fa[x] < 0) return x;

20     return fa[x] = find(fa[x]);

21 }

22 

23 void merge(int a, int b)

24 {

25     int x = find(a);

26     int y = find(b);

27     if (x < y) {

28         fa[x] += fa[y];

29         fa[y] = x;

30     }

31     if (x > y) {

32         fa[y] += fa[x];

33         fa[x] = y;

34     }

35 }

36 

37 void judge(int i, int j, int x, int y)

38 {

39     if (y < m && s[a[i][j] - 'A'][2] == '1' && s[a[i][y] - 'A'][0] == '1') 

40         merge(i*m + j, i*m + y);

41     if (x < n && s[a[i][j] - 'A'][3] == '1' && s[a[x][j] - 'A'][1] == '1')

42         merge(i*m + j, x*m + j);

43 }

44 

45 

46 void init()

47 {

48     memset(fa,-1,sizeof(fa));

49     num = 0;

50 }

51 

52 int main()

53 {

54     while (cin >> n >> m) {

55         if (n < 1 || m < 1) break;

56         init();

57         for (int i = 0; i < n; ++i){

58             a[i].clear();

59             cin >> a[i];

60         }

61         for (int i = 0; i < n; ++ i)

62             for (int j = 0; j < m; ++j) {

63                 int x = i + 1;

64                 int y = j + 1; 

65                 judge(i,j,x,y);

66             }

67         for (int i = 0; i < n*m; ++i)

68             if (fa[i] < 0) num++;

69             //cout << fa[i] << " ";

70         cout << num << endl;

71     }

72     return 0;

73 }