C primer plus课后编程练习答案

n\

return 0; }

下面是一些输出示例：

Enter 0 for metric mode, 1 for US mode: 0 Enter distance traveled in kilometers: 600 Enter fuel consumed in liters:

Fuel consumption is liters per 100 km.

Enter 0 for metric mode, 1 for US mode (-1 to quit): 1 Enter distance traveled in miles: 434 Enter fuel consumed in gallons: Fuel consumption is miles per gallon.

Enter 0 for metric mode, 1 for US mode (-1 to quit): 3 Invalid mode specified. Mode 1(US) used. Enter distance traveled in miles: 388 Enter fuel consumed in gallons: Fuel consumption is miles per gallon.

Enter 0 for metric mode, 1 for US mode (-1 to quit): -1 Done.

如果用户键入了不正确的模式，程序向用户给出提示信息并选取最接近的模式。请提供一个头文件和源代码文件，来使程序可以运行。源代码文件应定义3个具有文件作用域、内部链接的变量。一个代表模式，一个代表距离，还有一个代表消耗的燃料。函数get_info()根据模式设置提示输入相应的数据，并将用户的回答存入文件作用域变量。函数show_info()根据所选的模式计算并显示燃料消耗值。

Mode %s used.\\n\ }

void get_info(void) {

if (present_mode==METRIC) {

printf (\ scanf (\

printf (\

scanf (\ } else {

printf (\ scanf (\

printf (\ scanf (\ } }

void show_info(void) {

if (present_mode==METRIC)

printf (\ else

printf (\ } n\

return 0; }

Mode %s used.\\n\ }

void get_info(int mode, int present_mode, double *p_disance, double *p_fuel) {

if (present_mode==METRIC) {

printf (\ scanf (\

printf (\

scanf (\ } else {

printf (\ scanf (\

printf (\ scanf (\ } }

void show_info(int present_mode, double distance, double fuel) {

if (present_mode==METRIC)

printf (\ else

printf (\ } n\

return 0; } 18

How many sides and how many dice? 6 3

Here are 18 sets of 3 6-sided throws.

12 10 6 9 8 14 8 15 9 14 12 17 11 7 10 13 8 14

How many sets? Enter q to stop. q

#include <> #include <> #include <>

int main(void) {

char set,side,dice,i,sum;

puts(\ while(scanf(\ {

srand( time(0) );

puts(\ while(scanf(\ {

scanf(\ while (set--) {

for (i=0,sum=0; i

puts(\ }

return 0; }

8．下面是某程序的一部分： n\

return 0; }

给出函数make_array()和show_array()的定义以使程序完整。函数make_array()接受两个参数。第一个是int数组的元素个数，第二个是要赋给每个元素的值。函数使用malloc()来创建一个适当大小的数组，把每个元素设定为指定的值，并返回一个数组指针。函数show_array()以8个数一行的格式显示数组内容。

#include <> #include <>

int * make_array (int elem, int val); void show_array (const int ar[], int n);

int main(void) {

int * pa; int size; int value;

printf (\ scanf (\ while (size > 0) {

printf (\ scanf (\

pa = make_array (size, value); if (pa) {

show_array (pa,size); free(pa); }

printf(\ scanf(\ }

printf(\ return 0; }

int * make_array (int elem, int val) { int *p;

p = (int *)malloc( elem * sizeof(int) ); while(elem--) *(p + elem) = val; return p; }

void show_array (const int ar[], int n) { int i;

for (i=0;i

printf(\ if(i%8==7) printf(\ } }