（完整word版）CPrimerPlus第6版编程练习答案（已下载）

C Primer Plus Sixth Edition Programming Exercise

Selected Answers

if (limit > 1)

printf(\else

printf(\for (num = 2; num <= limit; num++) {

for (div = 2, numIsPrime = true; (div * div) <= num; div++) if (num % div == 0) numIsPrime = false; if (numIsPrime)

printf(\ }

printf(\ }

printf(\return 0; }

PE 7---11

/* pe7-11.c */

/* Programming Exercise 7-11 */ #include

#include int main(void) {

const double price_artichokes = 2.05; const double price_beets = 1.15; const double price_carrots = 1.09; const double DISCOUNT_RATE = 0.05; const double under5 = 6.50; const double under20 = 14.00; const double base20 = 14.00; const double extralb = 0.50; char ch;

double lb_artichokes = 0; double lb_beets = 0; double lb_carrots = 0; double lb_temp; double lb_total; double

cost_artichokes; double cost_beets; double cost_carrots; double cost_total; double final_total; double discount; double shipping;

printf(\printf(\getchar()) != 'q' && ch != 'Q') { if (ch == '\\n') continue; while

(getchar() != '\\n') continue; ch =

tolower(ch); switch (ch) {

case 'a' : printf(\scanf(\+= lb_temp; break;

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C Primer Plus Sixth Edition Programming Exercise

Selected Answers

case 'b' : printf(\scanf(\+= lb_temp; break;

case 'c' : printf(\

carrots: \lb_carrots += lb_temp; break;

default : printf(\ }

printf(\printf(\ }

cost_artichokes = price_artichokes * lb_artichokes; cost_beets = price_beets * lb_beets; cost_carrots =

price_carrots * lb_carrots; cost_total = cost_artichokes + cost_beets + cost_carrots; lb_total = lb_artichokes + lb_beets + lb_carrots; if (lb_total <= 0) shipping = 0.0; else if (lb_total < 5.0) shipping = under5; else if (lb_total < 20) shipping = under20; else shipping = base20 + extralb * lb_total; if (cost_total > 100.0)

discount = DISCOUNT_RATE * cost_total; else discount = 0.0;

final_total = cost_total + shipping - discount; printf(\

printf(\lb_artichokes, price_artichokes, cost_artichokes);

printf(\lb_beets, price_beets, cost_beets); printf(\carrots at $%.2f per pound: $%.2f\\n\price_carrots, cost_carrots); printf(\

vegetables: $%.2f\\n\ printf(\printf(\

printf(\return 0; }

Chapter 8 Programming Exercises

PE 8---1

/* Programming Exercise 8-1 */ #include

int main(void) { int ch; int ct = 0; while ((ch = getchar()) != EOF) ct++;

printf(\ return 0; }

PE 8---3

/* Programming Exercise 8-3 */

/* Using ctype.h eliminates need to assume consecutive coding */ #include

#include int

main(void) { int ch;

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C Primer Plus Sixth Edition Programming Exercise

Selected Answers

unsigned long uct = 0; unsigned long lct = 0; unsigned long oct = 0;

while ((ch = getchar()) != EOF) if (isupper(ch)) uct++; else if (islower(ch)) lct++; else oct++;

printf(\

printf(\other characters read\\n\ return 0; }

/* or you could use if

(ch >= 'A' && ch <= 'Z') uct++;

else if (ch >= 'a' && ch <= 'z') lct++; else oct++; */

PE 8---5

/* Programming Exercise 8-5 */

/* binaryguess.c -- an improved number-guesser */ /* but relies upon truthful, correct responses */ #include #include int main(void)

{ int high = 100; int low = 1; int guess = (high + low) / 2; char response;

printf(\

printf(\h if it is high, and with an l if it is low.\\n\number %d?\\n\

while ((response = getchar()) != 'y') /* get response */ {

if (response == '\\n') continue;

if (response != 'h' && response != 'l') {

printf(\printf(\ }

if (response == 'h') high = guess - 1; else if (response == 'l') low = guess + 1; guess = (high + low) / 2;

printf(\ }

printf(\return 0; }

PE 8---7

/* Programming Exercise 8-7 */

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C Primer Plus Sixth Edition Programming Exercise

Selected Answers

#include #include #include

#define BASEPAY1 8.75 // $8.75 per hour #define BASEPAY2 9.33 // $9.33 per hour #define BASEPAY3 10.00 // $10.00 per hour #define BASEPAY4 11.20 // $11.20 per hour #define BASEHRS 40 // hours at basepay #define OVERTIME 1.5 // 1.5 time

#define AMT1 300 // 1st rate tier #define AMT2 150 // 2st rate tier

#define RATE1 0.15 // rate for 1st tier #define RATE2 0.20 // rate for 2nd tier #define RATE3 0.25 // rate for 3rd tier int getfirst(void); void menu(void); int main(void) { double

hours; double gross; double net; double taxes; double pay; char response; menu();

while ((response = getfirst()) != 'q') {

if (response == '\\n') /* skip over newlines */ continue;

response = tolower(response); /* accept A as a, etc. */ switch (response) {

case 'a': pay = BASEPAY1; break; case 'b': pay = BASEPAY2; break; case 'c': pay = BASEPAY3; break; case 'd': pay = BASEPAY4; break;

default : printf(\menu();

continue; // go to beginning of loop }

printf(\scanf(\gross = hours * pay; else

gross = BASEHRS * pay + (hours - BASEHRS) * pay * OVERTIME; if (gross <= AMT1) taxes = gross * RATE1; else if (gross <= AMT1 + AMT2)

taxes = AMT1 * RATE1 + (gross - AMT1) * RATE2; else

taxes = AMT1 * RATE1 + AMT2 * RATE2 + (gross - AMT1 - AMT2) * RATE3; net = gross - taxes;

printf(\net); menu(); } printf(\ return 0; }

void menu(void) {

printf(\ \

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C Primer Plus Sixth Edition Programming Exercise

Selected Answers

printf(\ \

printf(\BASEPAY2);

printf(\BASEPAY4); printf(\

printf(\ \}

int getfirst(void) { int ch;

ch = getchar(); while (isspace(ch)) ch = getchar(); while (getchar() != '\\n') continue; return ch; }

Chapter 9 Programming Exercises

PE 9---1

/* Programming Exercise 9-1 */ #include

double min(double, double); int main(void) {

double x, y; printf(\numbers (q to quit): \(scanf(\

{ printf(\

min(x,y)); printf(\\ }

printf(\ return 0; }

double min(double a, double b) {

return a < b ? a : b; }

/* alternative implementation double min(double a, double b) { if (a < b) return a; else return b; } */

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