字符串的模式匹配算法

#include<stdio.h>#define N1 11#define N2 6void kmp(char *p,char *q,int *next);void basicIndex(char *p,char *q){int i=0,j=0,pos;while(i<N1&&j<N2){if(p[i]==q[j]){i++;j++;}else{i=i-j+1;j=0;}}if(j>=N2){pos=i-j;}elsepos=-1;printf("%d",pos);}//basic next of KMPvoid getNext(char *p,char *q){int i=0,j=-1,next[N2];next[0]=-1;while(i<N2){if(j==-1||q[i]==q[j]){i++;j++;next[i]=j;}else{j=next[j];}}kmp(p,q,next);}//improved nextvar of KMPvoid getNextVar(char *p,char *q){int i=0,j=-1,nextvar[N2];nextvar[0]=-1;while(i<N2){if(j==-1||q[i]==q[j]){i++;j++;if(q[i]!=q[j]){nextvar[i]=j;}else{nextvar[i]=nextvar[j];}}else{j=nextvar[j];}}kmp(p,q,nextvar);}void kmp(char *p,char *q,int *next){int i=0,j=0,pos=0;while(i<N1&&j<N2){if(j==-1||p[i]==q[j]){i++;j++;}else{j=next[j];}}if(j>=N2){pos=i-j;}else{pos=-1;}printf("%d",pos);}void main(){char *p={"00000000001"};char *q={"000001"};getNext(p,q);}