Question

如果三个if语句中的任何一个为真，则尝试退出程序，但仅在处理完所有三个语句之后才尝试退出程序。我已经通过多种方式对其进行了格式化，但我只能在每个语句后退出，而不是在所有三个语句之后退出。所以基本上它将继续使用其余的函数，即使其中两个if语句都是真的。

 int getValues(float* loan, float* rate, int* years)
 {

//Prompt the user for the loan amount, the yearly interest rate, and the loan length in years, then make sure each value is large enough

  printf("Enter a loan amount (dollars and cents):         ");
  scanf("%f", loan);
  printf("Enter a yearly interest rate (ex. 2.5 for 2.5%): ");
  scanf("%f", rate);
  printf("Enter the loan length in years (integer number): ");
  scanf("%d", years);
   if (*loan < 1)
       printf("\nStarting amount must be at least one dollar.\n");

   if (*rate < .1)
       printf("Interest rate must be at least .1%.\n");

   if (*years < 1)
   {   printf("Number of years must be at least 1.\n");
       exit (100);
   }

  return(0); 
}

这只是最近的一次尝试。我对编程非常陌生，并且在这个小程序上花费了无数个小时。

Answer 1

您需要添加一个标志变量，您将在每个system.file("sql/myquery.sql",package = "mypackage")的正文中设置该变量。然后你会检查标志和if是否已设置。

exit

Answer 2

使用标志，这是一种简单的方法，可以在您不想立即采取行动时跟踪特定条件。

int flag = 0;
if (*loan < 1)
{
    printf("\nStarting amount must be at least one dollar.\n");
    flag = 1;
}

if (*rate < .1)
{
    printf("Interest rate must be at least .1%.\n");
    flag = 1;
}

if (*years < 1)
{   
    printf("Number of years must be at least 1.\n");
    flag = 1;
}

if(flag == 1)
{
    exit(100)
}

Answer 3

我有一个初始化为false的布尔变量，然后当一个条件被命中时，设置为true。然后在最后进行简单的布尔检查。

int getValues(float* loan, float* rate, int* years)
{
  int shouldExit = 0;
  //Prompt the user for the loan amount, the yearly interest rate, and the loan length in years, then make sure each value is large enough

  printf("Enter a loan amount (dollars and cents):         ");
  scanf("%f", loan);
  printf("Enter a yearly interest rate (ex. 2.5 for 2.5%): ");
  scanf("%f", rate);
  printf("Enter the loan length in years (integer number): ");
  scanf("%d", years);
  if (*loan < 1){
   shouldExit = 1;
   printf("\nStarting amount must be at least one dollar.\n");
  }
  if (*rate < .1){
   shouldExit = 1;
   printf("Interest rate must be at least .1%.\n");
  }
  if (*years < 1)
  {   printf("Number of years must be at least 1.\n");
      shouldExit = 1;
  }

  if (shouldExit == 1){
      exit (100);
  }

  return(0); 
}

Answer 4

int errors = 0;
if (*loan < 1) {
       printf("\nStarting amount must be at least one dollar.\n");
       errors = 1;
}
..

像上面设置的变量错误或任何变为1.后来检查并退出。 ..

如果这三个陈述中的任何一个都是真的，我如何让C退出程序？但是在处理了所有三个陈述之后？

4 个答案: