POJ 2965 the pilots ' refrigerator

Original title Link: http://poj.org/problem?id=2965

Simple DFS, because it is required minimum value, enumeration depth to get the recursive termination condition, and poj1753 very much like, after all, is put together.

2. #include <iostream>
4. #include <cstdio>
6. #include <queue>
8. #include <cstring>
10. #include <cmath>
12. #include <cstdlib>
14. #include <vector>
16. #include <string>
18. #define CLR (arr) memset (arr,0,sizeof(arr))
20. #define N 100001
22. #define MOD 1e9+7
24. //#define LOCAL
26. typedef LONG long ll;
28. using namespace std;
30. int cmp (const void*c,const void*d) {return 1;} //above a lot of basic no eggs, just to use the time no more dozen, anyway compile too long and not suffer
32. Char handle[4][4];
34. int h[6][6];
36. int step,flag,fa[2][50],top;
38. void Flip (int row,int col) {
40. for (int i=1;i<=4;i++) h[i][col]^=1;
42. for (int j=1;j<=4;j++) if (J!=col) H[row][j]^=1; //Make the row flip with the column
44. return;
46. }
48. bool isopen () {
50. for (int i=1;i<=4;i++)
52. for (int j=1;j<=4;j++)
54. if (H[i][j]) return false;
56. return true; //Determine if it is open
58. }
60. void dfs (int row,int col,int deep) {
62. if (Deep==step) {
64. if (IsOpen ()) {
66. printf ("%d\n", step);
68. for (int i=0;i<top;i++) printf ("%d%d\n", Fa[0][i],fa[1][i]);
70. flag=1;
72. }
74. return;
76. }
78. if (Flag| | row==5)return ;
80. Fa[0][top]=row;
82. Fa[1][top++]=col; //Save the path, in fact, you can change the DFS to take the int return value, add judgment to save, perhaps also can reduce time
84. Flip (Row,col);
86. if (col<4)
88. DFS (ROW,COL+1,DEEP+1);
90. Else
92. DFS (ROW+1,1,DEEP+1);
94. top--;
96. Flip (Row,col);
98. if (col<4)
100. DFS (ROW,COL+1,DEEP);
102. Else
104. DFS (ROW+1,1,DEEP);
106. return;
108. }
110. int Main ()
112. {
114. #ifdef LOCAL
116. Freopen ("input.txt", "R", stdin);
118. //freopen ("Output.txt", "w", stdout);
120. #endif
122. for (int i=0;i<4;i++) {
124. scanf ("%s", Handle[i]);
126. for (int j=1;j<=4;j++) h[i+1][j]= (handle[i][j-1]== ' + ');
128. }
130. for (Step=1;; step++) {
132. DFS (1,1,0);
134. if (flag) break;
136. }
138. return 0;
140. }

I can spit groove I actually do not understand what is the content of the surface? In fact, this water problem is not too shy to put up, but as a souvenir, after all, POJ training first gun.

POJ 2965 the pilots ' refrigerator