1、实现strcpy函数

 

#include <stdio.h>//简单实现strcpy函数
char *my_strcpy(char *des, const char *src)
{if (des == NULL || src == NULL)return des;char *result = des;while ((*des++ = *src++) != '\0');return result;
}int main()
{char des[20];const char *src = "chenyu";printf("des is %s, and my_strcpy result is %s\n", des, my_strcpy(des, src));return 0;
}

 

结果：

 

des is chenyu, and my_strcpy result is chenyu

 

 

 

 

 

 

 

 

 

2、实现 strcat函数

 

#include <stdio.h>//简单实现strcat函数
char *my_strcat(char *des, const char *src)
{if (des == NULL || src == NULL)return des;char *result