C语言的多级指针你了解吗

int main(int argc,char **argv)
{
    for (int i = 0; i < argc; i++)
    {
            printf("argv[%d]=%s \n",i,argv[i]);
    }
    return 0;
}

$ gcc -o main main.c
$ ./main staging myname mypassword
argv[0]=./main 
argv[1]=staging 
argv[2]=myname 
argv[3]=mypassword 

int main(int argc,char **argv)
{
    int i = 0;
    while (argv[i]!=NULL)
    {
       printf("argv[%d]=%s \n",i,argv[i]);
       i++;
    }
    return 0;
}

$ gcc -o main main.c
$ ./main staging myname mypassword
argv[0]=./main 
argv[1]=staging 
argv[2]=myname 
argv[3]=mypassword 

int main()
{
    char **a;
    char a1 = 1;
    char a2 = 2;
    char a3 = 3;
    a[0] = &a1;
    a[1] = &a2;
    a[2] = &a3;
    //a[0]:1,a[1]:2,a[2]:3
    printf("a[0]:%d,a[1]:%d,a[2]:%d", a[0][0], *a[1], *a[2]);
    return 0;
}

    char *a[5];
    char a1 = 1;
    char a2 = 2;
    char a3 = 3;
    a[0] = &a1;
    a[1] = &a2;
    a[2] = &a3;
    //a[0]:1,a[1]:2,a[2]:3
    printf("a[0]:%d,a[1]:%d,a[2]:%d", a[0][0], *a[1], *a[2]);
    return 0;