C Primer Plus 第四章编程练习

C Primer Plus 第四章编程练习，便于理解课本，有助于期末考试复习和背诵。可收藏，亦可使用后补充知识点，完善属于自己的知识框架。

C Primer Plus 第四章编程练习

• 第一题
  • #include <stdio.h> int main() { printf("Please enter your first and last name: "); char first_name[40]; char last_name[40]; scanf("%s %s", first_name, last_name); printf("Your name: %s,%s", last_name, first_name); return 0; }
• 第二题
  • #include <stdio.h> #include <string.h> int main() { printf("Please enter your name: "); char first_name[40]; char last_name[40]; scanf("%s %s", first_name, last_name); int cnt_first, cnt_last; cnt_first = strlen(first_name); cnt_last = strlen(last_name); printf("Your last name is \"%s\", first name is \"%s\".\n", last_name, first_name); printf("Your last name is \"%20s\", first name is \"%20s\".\n", last_name, first_name); printf("Your last name is \"%-20s\", first name is \"%-20s\".\n", last_name, first_name); printf("Your last name is \"%*s\", first name is \"%*s\".\n", cnt_last + 3, last_name, cnt_first + 3, first_name); return 0; }
• 第三题
  • #include <stdio.h> int main() { float num; scanf("%f", &num); printf("Decimal form: %+.3f\n",num); printf("Exponential form: %.3E\n", num); return 0; }
• 第四题
  • #include <stdio.h> int main() { printf("Please enter your height in inch and name: "); float height; char name[40]; scanf("%f %s", &height, name); printf("%s, you are %.3f feet tall\n", name, height / 12); return 0; }
• 第五题
  • #include <stdio.h> int main() { printf("Please enter a download speed in megabits per second (Mb/sec) and a file size in megabytes (MB): "); float speed, file_size; scanf("%f %f", &speed, &file_size); float time; time = file_size * 8 / speed; printf("At %.2f megabits per second, a file of %.2f megabytes downloads in %.2f seconds.\n", speed, file_size, time); return 0; }
• 第六题
  • #include <stdio.h> #include <string.h> int main() { printf("Please enter your first name: "); char first_name[40]; scanf("%s", first_name); printf("Please enter your last name: "); char last_name[40]; scanf("%s", last_name); int cnt_first = strlen(first_name); int cnt_last = strlen(last_name); printf("%s %s\n", last_name, first_name); printf("%*d %*d\n", cnt_last, cnt_last, cnt_first, cnt_first); printf("%s %s\n", last_name, first_name); printf("%-*d %-*d\n", cnt_last, cnt_last, cnt_first, cnt_first); return 0; }
• 第七题
  • #include <stdio.h> #include <float.h> int main() { //FLT_DIG代表float有效十进制数字位数； //DBL_DIG代表double有效十进制数字位数; double d = 1.0 / 3.0; float f = 1.0 / 3.0; printf("float: %.6f\n",f); printf("float: %.12f\n", f); printf("float: %.16f\n", f); printf("double: %.6f\n",d); printf("double: %.12f\n", d); printf("double: %.16f\n", d); printf("FLT_DIG: %d\n", FLT_DIG); printf("DBL_DIG: %d\n", DBL_DIG); return 0; }
• 第八题
  • #include <stdio.h> #define GALLON_TO_LITRE 3.785 #define MILE_TO_KM 1.609 int main() { printf("Please enter the mileage of the trip and the amount of petrol consumed: "); float mileage; float petrol; scanf("%f %f", &mileage, &petrol); printf("Mileage per gallon: %.1f\n", mileage / petrol); printf("Litre per 100 km: %.1f\n", petrol * GALLON_TO_LITRE / ( mileage * MILE_TO_KM)); return 0; }