解决warning: incompatible implicit declaration of built-in function 'malloc'

由于代码中使用了malloc函数和字符串函数，编译时出现错误

warning: incompatible implicit declaration of built-in function ‘malloc’
warning: incompatible implicit declaration of built-in function ‘bzero’
warning: incompatible implicit declaration of built-in function ‘strncpy                                                                                                 ’
warning: incompatible implicit declaration of built-in function ‘strlen’

解决办法：

        加入头文件即可

#include<stdlib.h>

#include<string.h>