你能修改我的程序以在c中使用 "y/n"语句吗

Question

在这里，我正在编写一个 C 编程代码，我需要你们的帮助!我想修改我的程序并想在循环中使用它，即如果用户输入“y”并且如果输入“n”，则必须结束程序，我正在尝试使用 switch case，我尽力结束程序，它正在返回结束，但我不知道如何使用“y”值再次运行程序!

#include<conio.h>
#include<stdio.h>

int main()
{
   char n, A, B;
   float kmTOm = 0.621371;
   float inchesTOfoot = 0.0833333;
   float cmTOinches = 0.393701;
   float poundtokg = 0.453592;
   float inchesTOmeter = 0.0254;
   float a, b;
   while (1)
   {
      printf("Enter the input character. q to quit\n1. kms to miles\n2. inches to foot\n3. cms to inches\n4. pound to kgs\n5. inches to meters\n");

      scanf(" %c", &n);
      switch (n)
      {
      case 'q':
         printf("Quitting the program...");
         goto end;
         break;
      case '1':
         printf("Enter quantity in terms of a unit\n");
         scanf("%f", &a);
         b = a * kmTOm;
         printf("%.2f Kms is equal to %.2f Miles\n\n\n", a, b);
         break;
      case '2':
         printf("Enter quantity in terms of a unit\n");
         scanf("%f", &a);
         b = a * inchesTOfoot;
         printf("%f Inches is equal to %f Foot\n", a, b);
         break;
      case '3':
         printf("Enter quantity in terms of a unit\n");
         scanf("%f", &a);
         b = a * cmTOinches;
         printf("%f Cms is equal to %f Inches\n", a, b);
         break;
      case '4':
         printf("Enter quantity in terms of a unit\n");
         scanf("%f", &a);
         b = a * poundtokg;
         printf("%f Pounds is equal to Kgs %f \n", a, b);
         break;
      case '5':
         printf("Enter quantity in terms of a unit\n");
         scanf("%f", &a);
         b = a * inchesTOmeter;
         printf("%f inches is equal to %f meters \n", a, b);
         break;
      default:
         printf("In default now");
         break;
      }
   }
end:
   return 0;
}

我希望你们开发人员进行善意的修改来帮助我，因为我是一个初学者，学习了一个月，我除了实际的输出必须是这样的 ----o/p- do you Want to quit press "q”，你想再次运行按“y”

Answer 1

如果将 while(1) 更改为变量，则可以在每个循环后测试是否是时候退出。

我对您的代码所做的更改均在下面有注释:

#include<conio.h>
#include<stdio.h>

int main()
{
   char n, A, B;
   float kmTOm = 0.621371;
   float inchesTOfoot = 0.0833333;
   float cmTOinches = 0.393701;
   float poundtokg = 0.453592;
   float inchesTOmeter = 0.0254;
   float a, b;
   n = 'y';  //set n to make sure while repeats 
   while (n != 'n') //change while to test "n" instead of 1, this way the value of n can be changed and the loop can be exited
   {
      printf("Enter the input character. q to quit\n1. kms to miles\n2. inches to foot\n3. cms to inches\n4. po
und to kgs\n5. inches to meters\n");

      scanf(" %c", &n);
      switch (n)
      {
      case 'q':
         printf("Quitting the program...");
         return(0); //exit entire program
         break;
      case '1':
         printf("Enter quantity in terms of a unit\n");
         scanf("%f", &a);
         b = a * kmTOm;
         printf("%.2f Kms is equal to %.2f Miles\n\n\n", a, b);
         break;
      case '2':
         printf("Enter quantity in terms of a unit\n");
         scanf("%f", &a);
         b = a * inchesTOfoot;
         printf("%f Inches is equal to %f Foot\n", a, b);
         break;
      case '3':
         printf("Enter quantity in terms of a unit\n");
         scanf("%f", &a);
         b = a * cmTOinches;
         printf("%f Cms is equal to %f Inches\n", a, b);
         break;
      case '4':
         printf("Enter quantity in terms of a unit\n");
         scanf("%f", &a);
         b = a * poundtokg;
         printf("%f Pounds is equal to Kgs %f \n", a, b);
         break;
      case '5':
         printf("Enter quantity in terms of a unit\n");
         scanf("%f", &a);
         b = a * inchesTOmeter;
         printf("%f inches is equal to %f meters \n", a, b);
         break;
      default:
         printf("In default now");
         break;
      } 

        //Ask the user if they want to run again.  The code will exit if the user types 'n', it will repeat if they type anything else (including 'y').
        printf("\nRun again? y/n:");
        scanf(" %c",&n);

   } 

   return 0;
}