1 // HDOJ 2087 KMP算法
2 #include<iostream>
3 using namespace std;
4
5 #include<string>
6
7 void nextval(char s2[],int next[],int len)
8 {
9 next[1] = 0;
10 int i = 1,j = 0;
11 while(i < len)//这里是小于号而不是小于等于是因为里面有自加，防止越界！
12 {
13 if(j == 0 || s2[i] == s2[j])
14 {
15 ++i;
16 ++j;
17 if(s2[i] != s2[j]) next[i] = j;
18 else next[i] = next[j];
19 }
20 else j = next[j];
21 }
22 }
23
24 int KMP(char s1[],char s2[],int len1,int len2,int next[],int pos)
25 {
26 int i = pos,j = 1;
27 while(i <= len1 && j <= len2)
28 {
29 if(j == 0 || s1[i] == s2[j])
30 {
31 ++i;
32 ++j;
33 }
34 else j = next[j];
35 }
36 if(j > len2) return i;
37 else return 0;
38 }
39
40 int main()
41 {
42 string s1,s2;
43 while(cin>>s1 && s1 != "#")
44 {
45 cin>>s2;
46 int next[s2.size()+1],c = 0,pp = 0;
47 next[0] = -1;
48 char c1[s1.size()+1],c2[s2.size()+1];
49 for(int i = 1;i <= s1.size();++i) c1[i] = s1[i-1];
50 for(int i = 1;i <= s2.size();++i) c2[i] = s2[i-1];
51 nextval(c2,next,s2.size());
52 for(int pos = 1;pos <= s1.size();)
53 {
54 pp = KMP(c1,c2,s1.size(),s2.size(),next,pos);
55 if(pp)
56 {
57 ++c;
58 pos = pp;
59 }
60 else break;
61 }
62 cout<<c<<endl;
63 }
64
65 return 0;
66 }
