Question

2．编写函数fun(char *str，char *substr), 该函数可以统计长度为2的字符串在str所指的字符串中出现的次数

Answer 1

#include<stdio.h>
#include<string.h>
#include<stdlib.h>
int my_countsub(char *str,char *sub)
{
char *p,*q;
p=sub;
int c=0;
while(*str)
{
q=str;
while(*p==*q&&*q){p++;q++;}
if(*p=='\0')
c++;
p=sub;
str++;
}
return c;
}

void main()
{
char a[]="wad12fds12wd1122";
char b[]="12";
printf("%d\n",my_countsub(a,b));
}