HDU-2087-KMP-水题

纯KMP

 1 #include <cstdio>
 2 #include <algorithm>
 3 #include <cstring>
 4 #include <ctype.h>
 5 #include <cstdlib>
 6 #include <stack>
 7 #include <set>
 8 #include <map>
 9 #include <queue>
10 #include <string>
11 #include <cmath>
12 
13 
14 
15 using namespace std;
16 
17 int M,N,T;
18 char A[1000100],B[10100];
19 int f[10100];
20 
21 void getFail(char *P)
22 {        
23     f[0] = 0;f[1] = 0;
24     for(int i=1;i<M;i++)
25     {
26         int j = f[i];
27         while(j && P[i] != P[j]) j = f[j];
28         f[i+1] = P[i] == P[j] ? j+1 : 0;
29     }
30 }
31 
32 int find(char *T,char *P)
33 {
34     getFail(P);
35     int j=0;
36     int ans = 0;
37     for(int i=0;i<N;i++)
38     {
39         while(j && T[i] != P[j]) j = f[j];
40         if( T[i] == P[j] ) j++;
41         if(j == M) {i += M-1;ans++;}
42     }
43     return ans;
44 }
45 
46 
47 int main()
48 {
49     
50     while(2 == scanf("%s %s",A,B))
51     {
52         N = strlen(A);M = strlen(B);
53         printf("%d\n",find(A,B));
54     }
55 }

 

posted @ 2015-08-14 16:41  Helica  阅读(267)  评论(0)  编辑  收藏  举报