《C语言程序设计》第7章习题答案

1、选择题

（1）D（2）D（3）D（4）C（5）D（6）C（7）C（8）B（9）C（10）C（11）B（12）C （13）B（14）A（15）A（16）C

2、程序分析题

（1）Ling ning:19

Langping:21

Zhu jian hua:20

（2）2，65，A

（3）1，2

（4） 3.110000

50

（5）audition time is 08:30:00

（6）99

Xiaowang

90

87

3、程序设计题

（1）#include

struct date{

int day;

int month;

int year;

}

main()

{

int i,flag,dayth,day71;

struct date d1;

int month_day[]={0,31,28,31,30,31,30,31,31,30,31,30,31};

day71=1;

for(i=1;i<7;i++)

day71=day71+month_day[i];

puts("\nPlease enter year/month/day:");

scanf("%d/%d/%d",&d1.year,&d1.month,&d1.day);

dayth=d1.day;

for(i=1;i

dayth=dayth+month_day[i];

printf("%d days\n",day71-dayth);

}

（2）#include

main()

{

enum color{

red,yellow,blue,white,black

};

enum color i,j,k,pri;

int n,loop;

n=0;

for(i=red;i<=black;i++)

for(j=red;j<=black;j++)

if(i!=j)

{

for(k=red;k<=black;k++)

if((k!=i)&&(k!=j))

{

n=n+1;

printf("%-4d",n);

for(loop=1;loop<=3;loop++)

{

switch(loop)

{

case 1:pri=i;break;

case 2:pri=j;break;

case 3:pri=k;break;

default: break;

}

switch(pri)

{

case red:

printf("%-10s","red");break;

case yellow:

printf("%-10s","yellow");break;

case blue:

printf("%-10s","blue");break;

case white:

printf("%-10s","white");break;

case black:

printf("%-10s","black");break;

default: break;

}

}

printf("\n");

}

}

printf("\ntotal:%5d\n",n);

}

（3）#include

#define SIZE 5

main()

{

struct staff{

char name[20];

int salary;

int age;

}attend[SIZE];

struct staff *ap;

putchar('\n');

for(ap=attend;ap

{

printf("Please enter name salary and age:\n");

scanf("%s%d%d",ap->name,&(ap->salary),&(ap->age)); }

for(ap=attend;ap

{

ap->age++;

ap->salary*=(1+0.3);

}

for(ap=attend;ap

printf("\n%-10s %6d %3d",

(ap->name),(ap->salary),(ap->age));

}