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;    }