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1 /* hdoj 1987 */ 2 #include 
     
       3 #include 
      
        4 #include 
       
         5 #include 
        
          6 #include 
         
           7 using namespace std; 8  9 char s[505];10 char map[25][25];11 bool visit[25][25];12 int n, m, len;13 int dir[4][2] = {14     0,1, 1,0, 0,-1, -1,015 }; // right down left up16 17 bool check(int x, int y) {18     return x<0 || x>=n || y<0 || y>=m;19 }20 21 void solve() {22     int i, j, k, tmp;23     int d = 0;24     int t = n*m/5;25     int x, y, xx, yy;26     27     len = 0;28     memset(visit, false, sizeof(visit));29     30     x = 0, y = -1;31     while (t--) {32         k = 5;33         tmp = 0;34         while (k) {35             xx = x + dir[d][0];36             yy = y + dir[d][1];37             if (check(xx, yy) || visit[xx][yy]) {38                 d = (d+1) & 3;39                 continue;40             }41             visit[xx][yy] = true;42             tmp = (tmp<<1) + map[xx][yy]-'0';43             --k;44             x = xx;45             y = yy;46         }47         if (tmp == 0)48             s[len++] = ' ';49         else50             s[len++] = tmp + 'A' - 1;51     }52 }53 54 int main() {55     int t, tt;56     int i, j, k;57     58     #ifndef ONLINE_JUDGE59         freopen("data.in", "r", stdin);60     #endif61     62     scanf("%d", &t);63     for (tt=1; tt<=t; ++tt) {64         scanf("%d %d %s", &n, &m, s);65         k = 0;66         for (i=0; i