hdu2087kmp模板练习

Posted 2020-11-26 randy-lo

题目网址：http://icpc.njust.edu.cn/Problem/Hdu/2087/

代码：

 1 #include<bits/stdc++.h>
 2 using namespace std;
 3 typedef unsigned int ui;
 4 typedef long long ll;
 5 typedef unsigned long long ull;
 6 #define pf printf
 7 #define mem(a,b) memset(a,b,sizeof(a))
 8 #define prime1 1e9+7
 9 #define prime2 1e9+9
10 #define pi 3.14159265
11 #define lson l,mid,rt<<1
12 #define rson mid+1,r,rt<<1|1
13 #define scand(x) scanf("%llf",&x) 
14 #define f(i,a,b) for(int i=a;i<=b;i++)
15 #define scan(a) scanf("%d",&a)
16 #define dbg(args) cout<<#args<<":"<<args<<endl;
17 #define inf 0x3f3f3f3f
18 #define maxn 100010
19 int n,m,t;
20 char s[maxn],p[maxn],nxt[maxn];
21 void getnxt()
22 {
23     int plen=strlen(p);
24     int i=-1,j=0;
25     nxt[0]=-1;
26     while(j<plen)
27     {
28         if(i==-1||p[i]==p[j])
29         {
30             i++,j++;
31             if(p[i]==p[j])nxt[j]=nxt[i];
32             else nxt[j]=i;
33         }
34         else i=nxt[i];
35     }
36 }
37 int kmp()
38 {
39     int plen=strlen(p);
40     int slen=strlen(s);
41     int j=0,i=0;
42     int cnt=0;
43     while(i<slen)
44     {
45         if(j==-1||s[i]==p[j])i++,j++;
46         else j=nxt[j];
47         if(j==plen)
48         {
49             j=0,cnt++;
50         }
51     }
52     return cnt;
53 }
54 int main()
55 {
56     //freopen("input.txt","r",stdin);
57     //freopen("output.txt","w",stdout);
58     std::ios::sync_with_stdio(false);
59     while(scanf("%s",s))
60     {
61         if(!strcmp(s,"#"))break;
62         scanf(" %s",p);
63         getnxt();
64         pf("%d
",kmp());
65     }
66  }