Ancient Message (古埃及象形文字识别 Uva 1103)

 1 #include <cstdio>
 2 #include <cstring>
 3 #include <utility>
 4 #include <set>
 5 #include <algorithm>
 6 #include <vector>
 7 using namespace std;
 8 
 9 const int MAXN = 200 + 10;
10 bool pic[MAXN][MAXN], record[MAXN][MAXN];
11 const char *name = "WAKJSD";
12 int f[MAXN][MAXN], dx[] = {0, -1, 0, 1}, dy[] = {1, 0, -1, 0};
13 int cnt, H, W, T;
14 vector<pair<int, int> > startp;
15 
16 void init_read() {
17     char s[55]; cnt = 0; H += 2; int NW = 4 * W + 2;
18     memset(pic, 0, sizeof(pic));
19     memset(f, 0, sizeof(f));
20     memset(record, 0, sizeof(record));
21     startp.clear();
22     for (int i = 0; i < NW; i++) pic[0][i] = pic[H - 1][i] = 0;
23     for (int i = 0; i < H; i++) pic[i][0] = pic[i][NW - 1] = 0;
24     for (int i = 1; i < H - 1; i++) {
25         scanf("%s", s);
26         for (int j = 0; j < W; j++) {
27             int num = s[j] > ‘9‘ ? s[j] - ‘a‘ + 10 : s[j] - ‘0‘;
28             for (int k = 0; k < 4; k++) 
29                 if (num >= (1 << (3 - k))) { pic[i][j * 4 + k + 1] = 1; num -= (1 << (3 - k));}
30         }
31     }
32     W = NW;
33 }
34 
35 void colorization(int x, int y, bool c) {
36     f[x][y] = cnt;
37     for (int i = 0; i < 4; i++) {
38         int nx = x + dx[i], ny = y + dy[i];
39         if (nx >= 0 && ny >= 0 && nx < H && ny < W && pic[nx][ny] == c && !f[nx][ny])
40             colorization(nx, ny, c); 
41     }
42 }
43 void floodfill() {
44     for (int i = 0; i < H; i++) 
45         for (int j = 0; j < W; j++) 
46             if (!f[i][j]) { 
47                 cnt++; colorization(i, j, pic[i][j]); 
48                 if (pic[i][j]) startp.push_back(make_pair(i, j)); 
49             }
50 }
51 
52 void get_signiture(set<int> &signature, int x, int y) {
53     record[x][y] = 1;
54     for (int i = 0; i < 4; i++) {
55         int nx = x + dx[i], ny = y + dy[i];
56         if (nx >= 0 && ny >= 0 && nx < H && ny < W) {
57             if (f[nx][ny] != f[x][y]) signature.insert(f[nx][ny]);
58             else if(f[nx][ny] == f[x][y] && !record[nx][ny])
59                 get_signiture(signature, nx, ny); 
60         }
61     }
62 }
63 void recognize() {
64     vector<char> ans;
65     int n = startp.size();
66     for (int i = 0; i < n; i++) {
67         int x = startp[i].first, y = startp[i].second;
68         set<int> signature;
69         get_signiture(signature, x, y);
70         ans.push_back(name[signature.size() - 1]);
71     }
72     sort(ans.begin(), ans.end());
73     printf("Case %d: ", ++T);
74     for (int i = 0; i < n; i++)
75         printf("%c", ans[i]);
76     printf("\n");
77 }
78 
79 int main() {
80     while (scanf("%d%d", &H, &W) == 2 && H) {
81         init_read();
82         floodfill();
83         recognize();
84     }
85     return 0;
86 }