SDUT 2410 Mine Number(DFS)

题目链接

省赛的D题。。。。一年前的题目了。。。思路早就问过侯神了，就是讨论各种情况。。。早就想写一下，一直拖着。。今天乱写了一下。。终于过了。。写的太繁琐了，而且出现BUG了过不了样例，又加了一个判断，过了样例就AC了。。。

  1 #include <cstdio>

  2 #include <cstring>

  3 #include <cmath>

  4 #include <queue>

  5 using namespace std;

  6 int o[51][51],n,m,z;

  7 int a[4] = {0,0,1,-1};

  8 int b[4] = {1,-1,0,0};

  9 char p[31][31];

 10 int judge(int x,int y)

 11 {

 12     int i,t = 0;

 13     if(o[x][y])

 14     t ++;

 15     for(i = 0;i < 4;i ++)

 16     {

 17         if(x+a[i] >= 0&&x+a[i] < n&&y+b[i] >= 0&&y+b[i] < m)

 18         {

 19             if(o[x+a[i]][y+b[i]])

 20             t ++;

 21         }

 22     }

 23     if(t == p[x][y]-'0')

 24     return 1;

 25     else

 26     return 0;

 27 }

 28 void dfs(int x,int y)

 29 {

 30     int i,j,r,c,num,temp;

 31     if(x-2 >= 0)//判断一下已知的点是否符合

 32     {

 33         if(!judge(x-2,y))

 34         return ;

 35     }

 36     if(x == n)

 37     {

 38         z = 1;

 39         for(i = 0;i < n;i ++)

 40         {

 41             for(j = 0;j < m;j ++)

 42             {

 43                 if(o[i][j])

 44                 printf("*");

 45                 else

 46                 printf(".");

 47             }

 48             printf("\n");

 49         }

 50     }

 51     if(z) return ;

 52     if(y+1 == m)

 53     {

 54         r = x+1;

 55         c = 0;

 56     }

 57     else

 58     {

 59         r = x;

 60         c = y + 1;

 61     }

 62     if(x == n-1)

 63     {

 64         if(judge(x,y))

 65         dfs(r,c);

 66     }

 67     else if(o[x][y] != -1)

 68     {

 69         num = 0;

 70         temp = p[x][y] - '0';

 71         if(x-1 >= 0)

 72         num += o[x-1][y];

 73         if(y-1 >= 0)

 74         num += o[x][y-1];

 75         if(o[x][y])

 76         num ++;

 77         if(num > temp)

 78         return ;

 79         else if(num == temp)

 80         {

 81             o[x][y+1] = 0;

 82             o[x+1][y] = 0;

 83             if(judge(x,y))

 84             dfs(r,c);

 85         }

 86         else if(temp - num == 1)

 87         {

 88             o[x][y+1] = 1;

 89             o[x+1][y] = 0;

 90             if(judge(x,y))

 91             dfs(r,c);

 92             o[x][y+1] = 0;

 93             o[x+1][y] = 1;

 94             if(judge(x,y))

 95             dfs(r,c);

 96         }

 97         else if(temp - num == 2)

 98         {

 99             o[x][y+1] = 1;

100             o[x+1][y] = 1;

101             if(judge(x,y))

102             dfs(r,c);

103         }

104     }

105     else

106     {

107         num = 0;

108         temp = p[x][y] - '0';

109         if(x-1 >= 0)

110         num += o[x-1][y];

111         if(y-1 >= 0)

112         num += o[x][y-1];

113         if(num > temp)

114         return ;

115         else if(num == temp)

116         {

117             o[x][y] = 0;

118             o[x][y+1] = 0;

119             o[x+1][y] = 0;

120             if(judge(x,y))

121             dfs(r,c);

122         }

123         else if(temp - num == 1)

124         {

125             o[x][y] = 1;

126             o[x][y+1] = 0;

127             o[x+1][y] = 0;

128             if(judge(x,y))

129             dfs(r,c);

130             o[x][y] = 0;

131             o[x][y+1] = 1;

132             o[x+1][y] = 0;

133             if(judge(x,y))

134             dfs(r,c);

135             o[x][y] = 0;

136             o[x][y+1] = 0;

137             o[x+1][y] = 1;

138             if(judge(x,y))

139             dfs(r,c);

140         }

141         else if(temp - num == 2)

142         {

143             o[x][y] = 1;

144             o[x][y+1] = 1;

145             o[x+1][y] = 0;

146             if(judge(x,y))

147             dfs(r,c);

148             o[x][y] = 1;

149             o[x][y+1] = 0;

150             o[x+1][y] = 1;

151             if(judge(x,y))

152             dfs(r,c);

153             o[x][y] = 0;

154             o[x][y+1] = 1;

155             o[x+1][y] = 1;

156             if(judge(x,y))

157             dfs(r,c);

158         }

159         else if(temp - num == 3)

160         {

161             o[x][y] = 1;

162             o[x][y+1] = 1;

163             o[x+1][y] = 1;

164             if(judge(x,y))

165             dfs(r,c);

166         }

167     }

168     return ;

169 }

170 int main()

171 {

172 

173     int t,i,num = 0;

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

175     while(t--)

176     {

177         z = 0;

178         num ++;

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

180         memset(o,-1,sizeof(o));

181         for(i = 0; i < n; i ++)

182         scanf("%s",p[i]);

183         printf("Case %d:\n",num);

184         dfs(0,0);

185     }

186     return 0;

187 }

188 /*

189 3

190 2 2

191 21

192 21

193 */