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union
{
int i;
char x[2];
}a;
int main()
{
//a.x[0] = 10;
//a.x[1] = 1;
a.i = 1;
int i = 0;
int arr[32] = {};
for(i; i < 31; ++i)
{
if(a.i & (1 << i))
arr[i] = 1;
}
for(i = 0; i < 31; ++i)
printf("%d ", arr[i]);
if(a.x[0])
printf("小端模式\n");
else
printf("大端模式\n");
return 0;
}
#include <stdio.h>
#include <stdlib.h>
char buf[17];
union U {
unsigned short int aa;
struct {
unsigned int bb:7;//(bit 0-6)
unsigned int cc:6;//(bit 7-12)
unsigned int dd:3;//(bit 13-15)
};
} u;
void main() {
//bbbbbbbbbbbbbbbb
//iiiiiiiiiiiiiiii
//tttttttttttttttt
//111111
//5432109876543210
//::::::::::::::::
u.aa=0xE07F;//1110000001111111
printf("bb==%d,cc==%d,dd==%d\n",u.bb,u.cc,u.dd);
u.bb=0x41;
u.cc=0x21;//dddccccccbbbbbbb
u.dd=5; //1011000011000001
printf("aa==0x%04X==%016s(2)\n",u.aa,itoa(u.aa,buf,2));
}
//bb==127,cc==0,dd==7
//aa==0xB0C1==1011000011000001(2)