hdu 2087 kmp

//简单的kmp匹配,寻找子串的个数,找到一个之后移动相应的指针就行了 
#include<iostream>
using namespace std;
char a[1005];
char b[1005]; 
int next[1005];

void get_next(char const* ptrn,int plen,int* next){
    int i=0;
    next[i]=-1;
    int j=-1;
    while(i<plen-1){
        if(j==-1||ptrn[i]==ptrn[j]){
            ++i;
            ++j;
            next[i]=j;
        }else{
            j=next[j];
        }
    }
}

int kmp_search(char const* src,int slen,char const* patn,int plen,int const* next,int pos)
{
    int i=pos;
    int j=0;
    while(i<slen&&j<plen){
        if(j==-1||src[i]==patn[j]){
            ++i;
            ++j;
        }else{
            j=next[j];
        }
    }
    if(j>=plen)
        return i-plen;
    else
        return -1;
}

int main(){
    while(scanf("%s%s",a,b)&&strcmp(a,"#")!=0){
        int len1=strlen(a);
        int len2=strlen(b);                                               
        int res=0;
        get_next(b,len2,next);
        int pos=0;
        while(pos<len1){
            int move;
            if((move=kmp_search(a,len1,b,len2,next,pos))!=-1){
                res++;
                pos=move+len2;
            }
            else
                break;
        }
        cout<<res<<endl;
    }
    return 0;    
}

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