pointers on c 编程练习 6-2

编写一个函数，用于删除字符串中的固定字符

<textarea readonly="readonly" name="code" class="c"> 
#include<stdio.h>

#define TRUE 1
#define FALSE 0

int del_substr(char *str,char const *substr);

void main()
{
    char st[100],sb[100];
    gets(st);
    gets(sb);
    printf("%d\n",del_substr(st,sb));
    puts(st);

}

int del_substr(char *str,char const *substr)
{
    int flag;
    char *a,*b;
    flag = FALSE;
    b = substr;
    while(*str != '\0')
    {
        if(*str == *substr)
        {
            a = str;
            while(*str++ == *substr++ && *(substr+1)!='\0')
                ;
            if(*substr == '\0')
            {
                flag = TRUE;
                break;
            }
            substr = b;
        }
        str+=1;
        flag = FALSE;
    }
    if(!flag)
        return FALSE;
    else
    {
        while(*str != '\0')
        {
            *a++ = *str;
            str+=1;
        }
        *a = '\0';
        return TRUE;
    }
}
</textarea>