c - C编程:开关运行两次

我正在编写一个程序，该程序输入三个数字，然后计算一些不同的事物（每个事物必须具有其自身的功能）。该程序从告诉用户他们的选项并等待他们的输入开始。在执行任何一种情况后，程序将再次打印菜单，但它将使用默认情况，然后将打印菜单并要求输入。任何帮助将不胜感激。

#include <stdio.h>
#include <stdlib.h>

void greeting() {
    printf("Welcome to Dr. Computer's Mathatorium \n"); // this is a seperate function just because
    printf("Remember to use capital letters when selecting \n");
}

//This getNum function is used to the get the number
int getNum ()
{
    int a;

    printf("Enter your first integer:"); //tells user to input number
    scanf("%i", &a); //input

    return a;
}

// gets the sum of the numbers
int getSum (int f, int g, int h)
{
    return (f + g + h);
}

// gets the sum of the numbers
int getPro (int f, int g, int h)
{
    return (f * g * h);
}

// gets the sum of the numbers
int getAvg (int f, int g, int h)
{
    return (f * g * h)/3;
}

// gets the sum of the numbers
int getLow (int f, int g, int h)
{
    return (f + g + h); //NEEDS ADJUSTING
}

main()
{
    int first, second, third, sum, pro, avg, low;

    char choice;
    greeting ();
    do {
        printf("Main Menu\n");
        printf("A) Get Three Integers\n");
        printf("B) Display the Sum\n");
        printf("C) Display the Product\n");
        printf("D) Display the Average\n");
        printf("E) Display the lowest\n");
        printf("F) Quit\n");
        scanf("%c", &choice);

        //here comes the switches to route the choices
        switch(choice){
        case 'A':
            first = getNum ();
            second = getNum ();
            third = getNum ();
            printf("first is: %i\n", first);
            printf("second is: %i\n", second);
            printf("third is: %i\n", third);
            break;

        case 'B':
            sum = getSum (first, second, third);
            printf("sum is: %i\n", sum);
            break;

        case 'C':
            pro = getPro (first, second, third);
            printf("product is: %i\n", pro);
            break;

        case 'D':
            avg = getAvg (first, second, third);
            printf("average is: %i\n", avg);
            break;

        case 'E':
            avg = getAvg (first, second, third); //NOT DONE YET
            printf("average is: %i\n", avg); //REMEMBER TO FIX
            break;

        default:
            printf("INVALID CHOICE!\n");
            break;
        }
    } while (choice != 'F');

    return 0;
}

最佳答案

尝试以下代码，这是您的程序，但有一些更改：

#include <stdio.h>


void greeting() {

printf("Welcome to Dr. Computer's Mathatorium \n"); // this is a seperate function just because
printf("Remember to use capital letters when selecting \n");
}


int getNum () //This getNum function is used to the get the number
{
int a;

printf("Enter your first integer:"); //tells user to input number
scanf("%i", &a); //input

return a;
}
int getSum (int f, int g, int h) // gets the sum of the numbers
{ return (f + g + h);


}
int getPro (int f, int g, int h) // gets the sum of the numbers
{ return (f * g * h);


}
int getAvg (int f, int g, int h) // gets the sum of the numbers
{ return (f * g * h)/3;


}
int getLow (int f, int g, int h) // gets the sum of the numbers
{ return (f + g + h); //NEEDS ADJUSTING


}

int main(void)
{
   int first, second, third, sum, pro, avg;

char choice;
greeting ();
do {
printf("Main Menu\n");
printf("A) Get Three Integers\n");
printf("B) Display the Sum\n");
printf("C) Display the Product\n");
printf("D) Display the Average\n");
printf("E) Display the lowest\n");
printf("F) Quit\n");
fseek(stdin,0,SEEK_END); // change
choice = getc(stdin); // change
//scanf("%c", &choice);

//here comes the switches to route the choices
switch(choice){
    case 'A':
    case 'a': // change
        first = getNum ();
        second = getNum ();
        third = getNum ();
        printf("first is: %i\n", first);
        printf("second is: %i\n", second);
        printf("third is: %i\n", third);
        break;

    case 'B':
    case 'b': // change
        sum = getSum (first, second, third);
        printf("sum is: %i\n", sum);
        break;

    case 'C':
    case 'c': // change
        pro = getPro (first, second, third);
        printf("product is: %i\n", pro);
        break;

    case 'D':
    case 'd': // change
        avg = getAvg (first, second, third);
        printf("average is: %i\n", avg);
        break;

    case 'E':
    case 'e': // change
        avg = getAvg (first, second, third); //NOT DONE YET
        printf("average is: %i\n", avg); //REMEMBER TO FIX
         break;

    default:
        printf("INVALID CHOICE!\n");
        break;

}
} while (choice != 'F' && choice != 'f'); // change

   return 0;
}

关于c - C编程:开关运行两次，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/25831913/