#ifndef INDEXHEAD_H_INCLUDED#define INDEXHEAD_H_INCLUDED#include <stdio.h>#include <stdlib.h>#include <string.h>#define MAXLEN 255typedef char Sstring[MAXLEN + 1] ;int StrAssign( Sstring str , char* ps ) ;int StrLength( Sstring str ) ;int StrPrint( Sstring str ) ;int StrCompare( Sstring str1 , Sstring str2 ) ;int StrSub( Sstring sub , Sstring str , int pos , int length ) ;int StrIndex1( Sstring str , Sstring sub , int pos ) ;int StrIndex2( Sstring str , Sstring sub , int pos ) ;int StrIndex3( Sstring str , Sstring sub , int pos ) ;int GetNext( Sstring str , int next[] ) ;#endif // INDEXHEAD_H_INCLUDED 

#include "indexhead.h"int StrAssign( Sstring str , char* ps ){  int i = 0 ;  if( strlen( ps ) > MAXLEN )  {    printf( "ERROR!/n" ) ;    exit( 1 ) ;  }  str[i++] = strlen( ps ) ;  while( i <= strlen( ps ) )  {    str[i] = *( ps + i - 1 ) ;    i++ ;  }  return 0 ;}int StrPrint( Sstring str ){  int i = 1 ;  while( i <= str[0] )  {    printf( "%c" , str[i++] ) ;  }  printf( "/n" ) ;  return 0 ;}int StrLength( Sstring str ){  return str[0] ;}int StrCompare( Sstring str1 , Sstring str2 ){  int i = 1 ;  int ret = 0 ;  while( i <= str1[0] && i <= str2[0] )  {    ret = ( unsigned char )str1[i] - ( unsigned char )str2[i] ;    if( ret < 0 )    {      return -1 ;    }    else if( ret > 0 )    {      return 1 ;    }    else    {      i++ ;    }  }  if( i <= str1[0] )  {    return -1 ;  }  else if( i <= str2[0] )  {    return 1 ;  }  else  {    return 0 ;  }}int StrSub( Sstring sub , Sstring str , int pos , int length ){  if( pos < 1 || pos > str[0] || length < 0 || length > str[0] - pos + 1 )  {    printf( "ERROR!/n" ) ;    exit( 1 ) ;  }  int i = 1 ;  sub[0] = length ;  while( i <= length )  {    sub[i] = str[pos + i - 1] ;    i++ ;  }  return 0 ;}int StrIndex1( Sstring str , Sstring sub , int pos ){  pos = 1 ;  Sstring stemp ;  while( pos <= str[0] - sub[0] + 1 )  {    StrSub( stemp , str , pos , sub[0] ) ;    if( !StrCompare( stemp , sub ) )    {      return pos ;    }    pos++ ;  }  return 0 ;}int StrIndex2( Sstring str , Sstring sub , int pos ){  if( pos < 1 || pos > str[0] - sub[0] + 1 )  {    printf( "ERROR!/n" ) ;    exit( 1 ) ;  }  int i = pos ;  int j = 1 ;  while( ( i <= str[0] - sub[0] + 1 ) && ( j <= sub[0] ) )  {    if( str[i] == sub[j] )    {      i++ ;      j++ ;    }    else    {      i = i - j + 2 ;      j = 1 ;    }  }  if( j > sub[0] )  {    return i - sub[0] ;  }  return 0 ;}int GetNext( Sstring str , int next[] ){  int i = 1 ;  next[1] = 0 ;  int j = 0 ;  while( i < str[0] )  {    if( j== 0 || str[i] == str[j] )    {      ++i ;      ++j ;      next[i] = j ;    }    else    {      j = next[j] ;    }  }  return 0 ;}int StrIndex3( Sstring str , Sstring sub , int pos ){  int i = pos ;  int j = 1 ;  int next[ sub[0] ] ;  GetNext( sub , next ) ;  while( i <= str[0] && j <= sub[0] )  {    if( j == 0 || str[i] == sub[j] )    {      ++i ;      ++j ;    }    else    {      j = next[j] ;    }  }  if( j > sub[0] )  {    return i - sub[0] ;  }  return 0 ;}

#include "indexhead.h"int main(){  /*Sstring str ;  Sstring str1 ;  char* p = "hello" ;  StrAssign( str , p ) ;  StrAssign( str1 , "ahello" ) ;  StrPrint( str ) ;  int i = StrLength( str ) ;  printf( "%d/n" , i ) ;  int j = StrCompare( str , str1 ) ;  printf( "%d/n" , j ) ;  StrSub( str , str1 , 3 , 4 ) ;  StrPrint( str ) ;*/  /*Sstring str1 ;//驗證StrIndex1()  Sstring sub ;  StrAssign( str1 , "shfiodshfdghafhs" ) ;  StrAssign( sub , "dgh" ) ;  int i = StrIndex1( str1 , sub , 1 ) ;  printf( "%d/n" , i ) ;*/  /*Sstring str1 ;//驗證StrIndex2()  Sstring sub ;  StrAssign( str1 , "shfiodshfdghafhs" ) ;  StrAssign( sub , "dgh" ) ;  int i = StrIndex2( str1 , sub , 1 ) ;  printf( "%d/n" , i ) ;*/  Sstring str1 ;//驗證StrIndex3()  Sstring sub ;  StrAssign( str1 , "shfiodshfdghafhs" ) ;  StrAssign( sub , "dgh" ) ;  int i = StrIndex3( str1 , sub , 1 ) ;  printf( "%d/n" , i ) ;  return 0;}