c 查找A字符串在B字符串中是否存在，计算出现的次数

主要是应用了头文件<string.h>中的strstr函数
char *
     strstr(const char *s1, const char *s2);

查找是否存在:

 1 #include<stdio.h>
 2 #include<string.h>
 3 int main(void)
 4 {
 5     char str3[] = {"abcabcdababc"};
 6     char str4[] = "abc",*b;
 7     int count=0;
 8     int len = strlen(str4);
 9     b = strstr(str3,str4);
10     if(b)
11         printf("find!
");
12     else
13         printf("not find
");
14     return 0;
15 }

计算出现的个数:

 1 #include<stdio.h>
 2 #include<string.h>
 3 int main(void)
 4 {
 5     char str3[] = {"abcabcdababc"};
 6     char str4[] = "abc",*b;
 7     int count=0;
 8     int len = strlen(str4);
 9     b = strstr(str3,str4);
10     while(b)
11     {
12         count++;
13         b = strstr(b+len,str4);
14     }
15     printf("%d
",count);
16 
17     return 0;
18 }