头文件HString.h:
/*HString.h*/
#ifndef HSTRING_H_INCLUDED
#define HSTRING_H_INCLUDED
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define defaultSize 30
typedef struct
{
char *ch; /*顺序串的存储数组*/
int maxSize; /*字符串存储数组的最大长度*/
int n; /*顺序串的实际长度*/
} HString;
#endif /*HSTRING_H_INCLUDED*/
源文件HString.c:
/*HString.c*/
#include "HString.h"
HString *initStr ( HString *s )/*串初始化*/
{
s->ch = ( char *) malloc ( ( defaultSize+1 )*sizeof ( char ) ); /*动态分配*/
s->ch[0] = '\0';
s->maxSize = defaultSize;
s->n = 0; /*串s的最大容量和当前长度*/
return s;
}
void createStr ( HString *s, char *init )/*从字符数组init构造串s*/
{
s->maxSize = defaultSize;
s->ch = ( char *) malloc (( defaultSize+1 )*sizeof ( char ));
s->n = strlen ( init );
strcpy ( s->ch, init );
}
void copyStr ( HString *s, HString *t )/*把串t复制给串s*/
{
s->maxSize = defaultSize;
s->ch = ( char *) malloc ( ( defaultSize+1 )*sizeof ( char ) );
s->n = t->n;
strcpy ( s->ch, t->ch );
}
HString *subStr ( HString *s, int pos, int len )/*在串s中连续取从pos开始的len个字符,
构成子串返回。若提取失败则函数返回NULL*/
{
HString *tmp = ( HString * )malloc( sizeof(HString) );
tmp->ch = ( char *) malloc ( ( defaultSize+1 )*sizeof ( char ) );
tmp->maxSize = defaultSize;
if ( pos < 0 || len < 0 || pos+len-1 >= s->maxSize ) /*参数不合理,返回空串*/
{
tmp->n = 0;
tmp->ch[0] = '\0';
}
else
{
if ( pos+len-1 >= s->n )
len = s->n-pos; /*若提取个数超出串尾,修改个数*/
for ( int i = 0, j = pos; i < len; i++, j++)
tmp->ch[i] = s->ch[j];
tmp->n = len;
tmp->ch[len] = '\0';
}
return tmp;
}
void concat ( HString *s, HString *t )
{
/*将串t复制到串s后,串t不变。若完全连接成功,函数返回true;若部分连接成功,或
连接不成功,函数返回false*/
if ( s->n+t->n <= s->maxSize )/*原空间可容纳连接后的串*/
{
for ( int i = 0; i < t->n; i++ )
s->ch[s->n+i] = t->ch[i];
s->n = s->n+t->n;
s->ch[s->n] = '\0';
}
else
{ /*原空间容不下连接后的串*/
char *tmp = s->ch;
s->maxSize = s->n+t->n; /*暂存原串数组,算新串数组大小*/
s->ch = ( char* ) malloc ( ( s->maxSize+1 )*sizeof ( char ) );
strcpy ( s->ch, tmp );
strcat ( s->ch, t->ch ); /*复制原串s数组, 连接串t数组*/
s->n = s->n+t->n;
free ( tmp );
}
}
char getChar ( HString *s, int i )/*提取串s的第i个字符*/
{
if ( i < 0 || i >= s->n )
{
printf ( "字符串下标超界!\n" );
return '\0';
}
return s->ch[i];
}
void printStr ( HString *s )
{
printf ("打印串长度s->n=%d, 最大长度=%d\n", s->n, s->maxSize);
for ( int i = 0; i < s->n; i++ )
if ( s->ch[i] == '\0' )
break;
else
printf ( "%c", s->ch[i] );
printf("\n");
}
测试源文件test.c:
/*test.c*/
#include "HString.h"
#define defSize 30
/*
HefeiUniversityofTechnology
*/
int main ( )
{
char A[defSize] = {'H','e','f','e','i','U','n','i','v','e','r','s','i',
't','y','O','f','T','e','c','\0'};
char B[defSize] = {'H','e','f','e','i','U','n','i','v','e','r','s','i',
't','y','O','f','T','e','c','h','n','o','l','o','g','y','\0'};
HString *s1 = ( HString * )malloc( sizeof(HString) ), *s2 = ( HString * )malloc( sizeof(HString) ), *s3 = ( HString * )malloc( sizeof(HString) ), *s4 = ( HString * )malloc( sizeof(HString) );
s3 = initStr ( s3 );
s4 = initStr ( s4 );
printf ( "createString ( s1, A )\n" );
createStr ( s1, A );
printStr ( s1 );
printf ( "createString ( s2, B )\n" );
createStr ( s2, B);
printStr ( s2 );
printf ( "copy ( s3, s2 )\n" );
copyStr ( s3, s2 );
printStr ( s3 );
printf ( "s4 = subStr( s3, 5, 3 )\n" );
s4 = subStr( s3, 5, 3 );
printStr ( s4 );
printf ( "initString ( s4 )\n" );
initStr ( s4 );
printStr ( s4 );
printf ( "s4 = subStr ( s3, 8, 5 )\n" );
s4 = subStr ( s3, 8, 5 );
printStr ( s3 );
printStr ( s4 );
printf ( "concat ( s1, s4 )\n" );
concat ( s1, s4 );
printStr ( s1 );
printf ( "%c\n", getChar ( s1, 5 ) );
return 0;
}
程序运行截图: