可能比较绕口,那就是最低的地址存放高位字节,称为高位优先,最低的地址存放低位字节,成为低位优先

详细的内存察看如下：

代码:

#include <stdio.h> struct ss{ unsigned int i1:1; unsigned int i2:1; unsigned int i3:1; unsigned int i4:1; unsigned int i5:1; unsigned int i6:1; unsigned int i7:1; unsigned int i8:1; unsigned int j1:1; unsigned int j2:1; unsigned int j3:1; unsigned int j4:1; unsigned int j5:1; unsigned int j6:1; unsigned int j7:1; unsigned int j8:1; unsigned int k1:1; unsigned int k2:1; unsigned int k3:1; unsigned int k4:1; unsigned int k5:1; unsigned int k6:1; unsigned int k7:1; unsigned int k8:1; unsigned int l1:1; unsigned int l2:1; unsigned int l3:1; unsigned int l4:1; unsigned int l5:1; unsigned int l6:1; unsigned int l7:1; unsigned int l8:1; }; int main() { struct ss s; int j=1025; memcpy(&s,&j,4); printf("%d\n",sizeof(struct ss)); printf("%d%d%d%d%d%d%d%d\n",s.i1,s.i2,s.i3,s.i4,s.i5,s.i6,s.i7,s.i8); printf("%d%d%d%d%d%d%d%d\n",s.j1,s.j2,s.j3,s.j4,s.j5,s.j6,s.j7,s.j8); printf("%d%d%d%d%d%d%d%d\n",s.k1,s.k2,s.k3,s.k4,s.k5,s.k6,s.k7,s.k8); printf("%d%d%d%d%d%d%d%d\n",s.l1,s.l2,s.l3,s.l4,s.l5,s.l6,s.l7,s.l8); return 0; }