有如下一段代码（unit16_t为2字节无符号整数，unit8_t位1字节无符号整数）； union X { unint16_t a; struct Z { unint8_t m; unint8_t n; }z; }; union X x; x;a = 0x1234; 请问x.z.n在大字节序和小字节序机器上的值分别为多少（）？
union X { unint16_t a; struct Z { unint8_t m; unint8_t n; }z; }; union X x; x;a = 0x1234;
