HDU 2087 剪花布条 KMP

 1 // File Name: getnext.cpp
 2 // Author: darkdream
 3 // Created Time: 2014年09月09日 星期二 22时35分02秒
 4 
 5 #include<vector>
 6 #include<list>
 7 #include<map>
 8 #include<set>
 9 #include<deque>
10 #include<stack>
11 #include<bitset>
12 #include<algorithm>
13 #include<functional>
14 #include<numeric>
15 #include<utility>
16 #include<sstream>
17 #include<iostream>
18 #include<iomanip>
19 #include<cstdio>
20 #include<cmath>
21 #include<cstdlib>
22 #include<cstring>
23 #include<ctime>
24 #define LL long long
25 
26 using namespace std;
27 char str[1005];
28 char str1[1005];
29 int next[1005];
30 void getnext()
31 {
32     int len = strlen(str);
33     next[0] = -1; 
34     int k = -1;
35     int j = 0 ;
36     int sum = 0 ; 
37     while(j <= len - 1)
38     {
39         if(k == -1 || str[j] == str[k])
40         {
41             ++j; 
42             ++k;
43             next[j] = k ;
44         }
45         else {
46             k = next[k];
47         }
48     }
49 
50 }
51 void kmp()
52 {
53     getnext();
54     int lstr1 = strlen(str1);
55     int lstr = strlen(str);
56     int i = 0 ;
57     int j = 0 ;
58     int sum = 0 ;
59     while(j < lstr1)
60     {
61       if(i == -1 || str1[j] == str[i])
62       {
63         i ++ ; 
64         j ++; 
65       }else{
66         i  =  next[i];
67       }
68       if(i == lstr)
69       {
70         sum ++ ;
71       }
72     }
73     printf("%d\n",sum);
74 }
75 int main(){
76     while(scanf("%s",str1) != EOF)
77     {
78       if(strlen(str1) == 1  && str1[0] == ‘#‘)
79       {
80           break;
81       }
82       scanf("%s",str);
83     kmp();
84     }
85     
86     return 0;
87 }