1、删除子串，只要是原串中有相同的子串就删掉，不管有多少个，返回子串个数。

#include 
     
      #include 
      
       #include 
       
        #include 
        
         int delete_sub_str(const char *str,const char *sub_str,char *result){	assert(str != NULL && sub_str != NULL);	const char *p,*q;	char *t,*temp;	p = str;	q = sub_str;	t = result;	int n,count = 0;	n = strlen(q);	temp = (char *)malloc(n+1);	memset(temp,0x00,n+1);	while(*p)	{		memcpy(temp,p,n);		if(strcmp(temp,q) == 0 )		{			count++;			memset(temp,0x00,n+1);			p = p + n;		}		else		{				*t = *p;			p++;			t++;			memset(temp,0x00,n+1);		}		}	free(temp);	return count;}void main(){	char s[100] = {'\0'};　　　　 int num = delete_sub_str("123abc12de234fg1hi34j123k","123",s);	printf("The number of sub_str is %d\r\n",num);	printf("The result string is %s\r\n",s);	getchar();}