`size_t _strlen(const char *str) { size_t length = 0; while (*str++) length++; return (length); }` u should consider input arg ‘str’ is NULL ptr 。because if u operator NULL as *,u program will core dump in runnig
`size_t _strlen(const char *str)
{
size_t length = 0;
}`
u should consider input arg ‘str’ is NULL ptr 。because if u operator NULL as *,u program will core dump in runnig