C语言位段与联合体（union)的内存分配

union V {
struct X {
unsigned char s1:1;
unsigned char s2:1;
unsigned char s3:4;
} x;
unsigned char s1:1;
unsigned char s2:1;
unsigned char s3:4;
int c;
} v;
void main()
{

v.c = 100;  //0110 0100
printf("%d", v.x.s3); //9      内存从左到右依次分配
printf("%d", v.s3);  //4	内存都从最右边同一位置开始分配（共用）

system("pause");
}