最近在研读c primer plus,小白一枚，把自己做的答案写出来，望指正。
编程环境 visual studio 2010.第四章。
1 /* Programming Exercise 4-1 */
2 #include<stdio.h>
3 int main(void) 4 { 5 char fname[40]; 6 char lname[40]; 7 printf("please enter your first name\n"); 8 scanf("%s",&fname); 9 printf("please enter your last name\n"); 10 scanf("%s",&lname); 11 printf("%s,%s",fname,lname); 12 return 0; 13 }
1 /*programming exercise 4-2 */
2 #include <stdio.h>
3 #include<iostream> 4 5 int main(void) 6 { 7 char first_name[40]; 8 char last_name[40]; 9 int first_name_length = 0; 10 int last_name_lenght = 0; 11 printf("What's your first name:"); 12 scanf("%s", first_name); 13 14 printf("What's your last name:"); 15 scanf("%s", last_name); 16 17 getchar(); 18 19 first_name_length = strlen(first_name); 20 last_name_lenght = strlen(last_name); 21 22 printf("a.\"%s,%s\"\n", first_name, last_name); 23 printf("b.\"%20s,%20s\"\n", first_name, last_name); 24 printf("c.\"%-20s,%-20s\"\n", first_name, last_name); 25 printf("d.%*s,%*s\n", first_name_length+3, first_name, last_name_lenght+3, last_name); 26 27 return 0; 28 }
1 /*programming exercise 4-3*/
2 #include <stdio.h>
3 int main(void) 4 { 5 float n; 6 printf("enter a float number:\n"); 7 scanf("%f",&n); 8 printf("a. The input is%.1f or%.1e.\n",n,n); 9 printf("b.The input is +%.3f or %.3E.\n",n,n); 10 return 0; 11 }
1 /*programming exercise 4-4*/
2 #include <stdio.h>
3 #define CM_INCH 2.54 4 int main(void) 5 { 6 float height_cm=0; 7 float height_inch=0; 8 printf("enter your height:\n"); 9 scanf("%f",&height_inch); 10 getchar(); 11 printf("Dabney,you are %f feet tall\n",height_inch); 12 height_cm=height_inch*CM_INCH; 13 printf("Dabney,you are %f cm tall\n",height_cm); 14 return 0; 15 }
1 #include<stdio.h>
2 int main(void)
3 { 4 float speed=0; 5 float file_size=0; 6 float download_time; 7 printf("How much your network speed:"); 8 scanf_s("%f", &speed); 9 printf("How much is your download file:"); 10 scanf_s("%f", &file_size); 11 download_time = file_size / (speed / 8); 12 printf("At %f megabits per secnod, a file of %f magebytes\n download in %f seconds.\n", speed, file_size, download_time); 13 }
1 /*programming exercise 4-7*/
2 #include<stdio.h>
3 #include<float.h> 4 int main(void) 5 { 6 double d_value = 1.0 / 3.0; 7 float f_value = 1.0 / 3.0; 8 9 printf("the value of FLT_DIG:%d, the value of DBL_DIG:%d\n", FLT_DIG, DBL_DIG); 10 printf("the value of double:%.6lf, the value of float:%.6lf\n", d_value, f_value); 11 printf("the value of double:%.12lf, the value of float:%.12lf\n", d_value, f_value); 12 printf("the value of double:%.18lf, the value of float:%.18lf\n", d_value, f_value); 13 14 }
1 /*programming exercise 4-6*/
2 #include <stdio.h>
3 #include<iostream> 4 /*programming exercise 4-6*/ 5 int main(void) 6 { 7 char first_name[40] ; 8 char last_name[40] ; 9 int first_name_length = 0; 10 int last_name_length = 0; 11 12 printf("What's your first name:"); 13 scanf("%s", first_name); 14 printf("What's your last name:"); 15 scanf("%s", last_name); 16 first_name_length = strlen(first_name); 17 last_name_length = strlen(last_name); 18 printf("%s %s\n", first_name, last_name); 19 printf("%*d %*d\n", first_name_length, first_name_length, last_name_length, last_name_length); 20 printf("%s %s\n", first_name, last_name); 21 printf("%-*d %-*d\n", first_name_length, first_name_length, last_name_length, last_name_length); 22 }
1 /*programming exercise 4-8*/
2 #include <stdio.h>
3 #define KM_PER_MILE 1.609 4 #define PINT_PER_GALLON 3.785 5 int main(void) 6 { 7 float driven_distance = 0.0; 8 float gas_consumption = 0.0; 9 float pint_per_hundred_km = 0.0; 10 float mile_per_gallon = 0.0; 11 printf("How much distance have you traveled in kilometer:"); 12 scanf_s("%f", &driven_distance); 13 getchar(); 14 15 printf("How much gas have you used in pint:"); 16 scanf_s("%f", &gas_consumption); 17 getchar(); 18 19 pint_per_hundred_km = gas_consumption / driven_distance * 100; 20 mile_per_gallon = (driven_distance / KM_PER_MILE) / (gas_consumption / PINT_PER_GALLON); 21 22 printf("Fuel consumptions:%f pint/100km or %f mile/gallon\n", pint_per_hundred_km, mile_per_gallon); 23 }