CDZSC_2015寒假新人（4）——搜索 - N

 1 #include <stdio.h>
 2 #include <string.h>
 3 
 4 const int MAX = 128;
 5 
 6 struct URL{
 7     char a[MAX][MAX];
 8     int dir, max;
 9 
10     void create(){dir = 0; max = 0; memset(a, 0, sizeof(a)); strcpy(a[0], "http://www.acm.org/");}
11     bool back(){if(dir > 0)   {dir--; return true;} return false;}
12     bool fwd() {if(dir < max) {dir++; return true;} return false;}
13     void viw(char * str) {strcpy(a[++dir], str); max = dir;}
14     void show(){printf("%s\n", a[dir]);}
15 };
16 
17 URL url;
18 
19 int main()
20 {
21 #ifdef CDZSC_OFFLINE
22     freopen("in.txt", "r", stdin);
23     freopen("out.txt", "w", stdout);
24 #endif
25     char str[MAX];
26     url.create();
27     while(~scanf("%s", str))
28     {
29         switch(str[0])
30         {
31         case ‘V‘: scanf("%s", str); url.viw(str); url.show(); break;
32         case ‘F‘: if(url.fwd()) url.show(); else printf("Ignored\n"); break;
33         case ‘B‘: if(url.back()) url.show(); else printf("Ignored\n"); break;
34         case ‘Q‘: url.create(); break;
35         }
36     }
37     return 0;
38 }