【HDOJ】1601 Galactic Import

Dijkstra。

 1 /* 1601 */
 2 #include <cstdio>
 3 #include <cstring>
 4 #include <cstdlib>
 5
 6 #define INF 999999
 7
 8 char buf[27];
 9 int map[27][27];
10 bool visit[27], valid[27];
11 double val[27];
12 int path[27];
13 int n;
14
15 void dijkstra() {
16     int i, j, k;
17     int min, v;
18
19     memset(visit, false, sizeof(visit));
20     visit[26] = true;
21     for (i=0; i<27; ++i)
22         path[i] = map[i][26];
23
24     for (i=0; i<26; ++i) {
25         min = INF;
26         for (j=0; j<26; ++j) {
27             if (!visit[j] && path[j]<min) {
28                 min = path[j];
29                 v = j;
30             }
31         }
32         if (min == INF)
33             break;
34         visit[v] = true;
35         for (j=0; j<26; ++j) {
36             if (!visit[j] && path[j]>min+map[v][j]) {
37                 path[j] = min + map[v][j];
38             }
39         }
40     }
41 }
42
43 int main() {
44     int i, j, k, r;
45     double v, max;
46     char cmd[3], line[30];
47
48     #ifndef ONLINE_JUDGE
49         freopen("data.in", "r", stdin);
50         freopen("data.out", "w", stdout);
51     #endif
52
53     while (scanf("%d",&n)!=EOF) {
54         for (i=0; i<27; ++i) {
55             for (j=0; j<27; ++j) {
56                 map[i][j] = INF;
57             }
58             map[i][i] = 0;
59         }
60         for (i=0; i<n; ++i) {
61             scanf("%s %lf %s", cmd, &v, line);
62             j = cmd[0] - ‘A‘;
63             val[j] = v;
64             for (r=0; line[r]; ++r) {
65                 if (line[r] == ‘*‘)
66                     k = 26;
67                 else
68                     k = line[r] - ‘A‘;
69                 map[j][k] = map[k][j] = 1;
70             }
71         }
72         dijkstra();
73         max = -1;
74         v = 0;
75         for (i=0; i<26; ++i) {
76             if (path[i] >= INF)
77                 continue;
78             if (path[i] > 1) {
79                 j = path[i]-1;
80                 while (j--) {
81                     val[i] *= 0.95;
82                 }
83             }
84             if (val[i] > max) {
85                 max = val[i];
86                 v = i;
87             }
88         }
89         printf("Import from %c\n", (char)v+‘A‘);
90     }
91
92     return 0;
93 }