《C Primer Plus》第六版 第十二章编程练习答案

1.

#include

int critic(void );

int main(intargc, char *argv[]) {

intnum=56; int units;

printf(\); scanf(\,&units); while (units!=num) {

units=critic(); }

getchar(); return 0; }

int critic() {

int n;

printf(\); scanf(\, &n); return n; }

2.

//***********pe12-2a.h*******// #include

voidset_mode(int mode); voidget_info(); voidshow_info();

//**********pe12-2a.c*************// #include #include\

int mode;

float distance, fuel; voidset_mode(intm) {

if (m !=0 &&m !=1) {

printf(\); m=1; }

mode=m; }

voidget_info() {

if (0==mode) {

printf(\); scanf(\, &distance);

printf(\); scanf(\, &fuel); } else {

printf(\); scanf(\, &distance);

printf(\); scanf(\, &fuel); } }

voidshow_info() {

float units; if (0==mode) {

units=100* (fuel/distance);

printf(\, units); } else {

units=distance/fuel;

printf(\, units); } }

3.

//***********pe12-2a.h*******//

#include

voidset_mode(int mode); voidget_info(int mode);

voidshow_info(int mode, float distance, float fuel);

//***********pe12-2a.c*******// #include #include\

voidset_mode(intmode) {

if (mode !=0 &&mode !=1) {

printf(\); mode=1; }

get_info(mode); }

voidget_info(intmode) {

float distance, fuel; if (0==mode) {

printf(\); scanf(\, &distance);

printf(\); scanf(\, &fuel); } else {

printf(\); scanf(\, &distance);

printf(\); scanf(\, &fuel); }

show_info(mode, distance, fuel);

}

voidshow_info(intmode, floatdistance, floatfuel) {

float units; if (0==mode) {

units=100* (fuel/distance);

printf(\, units); } else {

units=distance/fuel;

printf(\, units); } }

//***********pe12-2b.c*******// #include #include\ int main(void) {

int mode;

printf(\); scanf(\, &mode); while(mode>=0) {

set_mode(mode);

printf(\); printf(\); scanf(\, &mode); }

printf(\); getchar(); return 0; }

4.

#include

int count=0;

int fun();

int main(void) {

inti=0; intcnt;

while (i<20) {

cnt=fun();

printf(\, cnt); i++; }

getchar(); return 0; }

int fun() {

count++; return count; }

5.

//*******main.c***************// #include #include\

int main(void) {

intStr[100]; int count;

for(count=0; count<100; count++) {

Str[count]=rand0(); }

sort(Str);

for (count=0; count<100; count++) {

if (count==0) {

putchar('\\n'); }