删除子字符串

#include <stdio.h>
#include <string.h>
int delete_sub_str(const char *str, const char *sub_str, char *result_str)
{
        int count=0;
        char *p1=str;
        char *pos=strstr(str,sub_str);
        while(pos!=NULL){
                count++;
                while(p1!=pos) *result_str++=*p1++;
                p1+=strlen(sub_str);
                pos=strstr(p1,sub_str);
        }
        while(*p1!='\0')
        {
                *result_str++=*p1++;
        }
        *result_str='\0';
        return count;
}
int main()
{
        char *p1="mabcoabctyuabcq";
        puts(p1);
        char *sub="abc";
        char res[20];
        int a=delete_sub_str(p1,sub,res);
        printf("res=%s and count=%d\n",res,a);
        return 0;
}