I’m ()to graduate in the next half of the year.

b)

main()

{

union{ /*定义一个联合*/

int i;

struct{ /*在联合中定义一个结构*/

char first;

char second;

}half;

}number;

number.i=0x4241; /*联合成员赋值*/

printf("%c%c\n", number.half.first,

mumber.half.second);

number.half.first='a'; /*联合中结构成员赋值

*/

number.half.second='b';

printf("%x\n", number.i);

getch();

}

●试题二

阅读下列函数说明和C代码，将应填入(n)处的字句写在答题纸的对应栏内。

【说明】

该程序运行后，输出下面的数字金字塔

【程序】

include<stdio．h>

main ()

{char max，next；

int i；

for(max=′1′；max<=′9′；max＋＋)

{for(i=1；i<=20- (1) ；＋＋i)

printf(" ")；

for(next= (2) ；next<= (3) ；next＋＋)

printf("％c"，next)；

for(next= (4) ；next>= (5) ；next--)

printf("％c"，next)；

printf("＼n")；

}

}

When you compare the differences between half-duplex and full-duplex Ethernet, which of the following characteristics are exclusive to half-duplex? (Select two answer choices)

A．Half-duplex Ethernet operates in a shared collision domain.

B．Half-duplex Ethernet operates in an exclusive broadcast domain.

C．Half-duplex Ethernet has efficient throughput.

D．Half-duplex Ethernet has lower effective throughput.

E．Half-duplex Ethernet operates in an exclusive collision domain.

执行下列语句后指针及链表的示意图为(43)。

L = (LinkList) malloc ( sizeof (LNode) );

P = L;

for(i =0;i ＜=3;i ++) {

P→next = (LinkList) malloc (sizeof (LNode));

P = P→next;

P→data = i * i + 1;

}

A．

B．

C．

D．

A. Half-duplex Ethernet operates in a shared collision domain.

B. Full-duplex Ethernet has a lower effective throughput.

C. Half-duplex Ethernet operates in a private collision domain.

D. Full-duplex Ethernet allows two-way communication.

E. Half-duplex Ethernet operates in a private broadcast domain.

#include "stdio.h"void half(void *pval,char type);main(){ int i=20; long l=100000; float ff=12.456; double d=123.044444; printf("%d\n",i); printf("%ld\n",l); printf("%f\n",ff); printf("%lf\n",d); half(&i,'i'); half(&l,'l'); half(&ff,'ff'); half(&d,'d'); printf("\n%d",i); printf("\n%ld",l); printf("\n%f",ff); printf("\n%lf",d); return 0; }void half(void *pval,char type){ switch(type) { case 'i': { *((int *)pval)/=2; //我想问一下，这个语法怎么理解，太复杂了 break; } case 'l': { *((long *)pval)/=2; break; } case 'ff': { *((float *)pval)/=2; break; } case 'd': { *((double *)pval)/=2; break; } } }