删除字符串中所有给定的子串

查了半天终于找到一个跟我思路相符的：

http://blog.sina.com.cn/s/blog_628821950100ynbu.html

 

char* my_strstr(char *str,char *sub)
{
    char *pstr,*psub,*ptmp;
    if(NULL == str || NULL == sub)
        return (char *)0;
    for(ptmp=str; *ptmp; ptmp++)
    {
        psub=sub;
        pstr=ptmp;
        while(*psub==*pstr && *psub!='\0')
        {
            psub++;
            pstr++;
        }
        if(*psub=='\0')
            return ptmp;
    }
    return NULL;
}

系统函数strstr()是这道题的灵感来源。

#include <stdio.h>

char* delsubstr(char *str, char *sub)
{
    char *ptmp,*pstr,*psub;
    char *pdst;

    if(NULL == str || NULL == sub)
        return (char *)0;
    pdst = str;
    pstr = str;
    while(*pstr)
    {
        ptmp = pstr;
        psub = sub;
        while( (*psub == *ptmp) && *ptmp )
        {
            psub++;
            ptmp++;
        }
        if('\0' == *psub)
        {
            pstr = ptmp;
        }
        else
        {
        // VC下会报错“写入0x...时发生访问冲突”
            *pdst++ = *pstr++;
        }
    }
    *pdst = '\0';

    return str;
}


void main()
{
    char str[40],sub[20];
    printf("Please input a string:\n");
    scanf("%s",str);
    printf("Please input the sub string:\n");
    scanf("%s",sub);

    printf("output string: %s\n", delsubstr(str, sub) );
}