c,while-loop,char,conditional , C Program - Basic Calculator


C Program - Basic Calculator

Question:

Tag: c,while-loop,char,conditional

I'm trying to write a basic calculator program in C, and I'm almost there! I have one issue though, and it's concerning repeatedly querying the user for input.

I can get through my loop once, but even though the user inputs the correct character, my program still breaks out of the loop.

I'm fairly new to C, but I've done a decent amount of programming in Java, so I understand the functionality of loops, conditionals, and data types.

#include <stdio.h>

int main()
{
    char yes;
    int a, b, c, choice;

    yes = 'y';
    while(yes == 'y' || yes == 'Y')
    {
        printf("Enter first integer: ");
        scanf("%d", &a);

        printf("Enter second integer: ");
        scanf("%d", &b);

        printf("\nAdd(1), Subtract(2), Multiply(3), Divide(4): ");
        scanf("%d", &choice);

        printf("\n");
        switch(choice) 
        {
                case(1):
                    c = a + b;
                    printf("%d + %d = %d\n", a, b, c);
                    break;
                case(2):
                    c = a - b;
                    printf("%d - %d = %d\n", a, b, c);
                    break;
                case(3):
                    c = a * b;
                    printf("%d * %d = %d\n", a, b, c);
                    break;
                case(4):
                    c = a / (float)b;
                    printf("%d / %d = %d\n", a, b, c);
                    break;
                default:
                    printf("Incorrect choice. Try again.\n");
        }

        printf("\nAgain (Y/N): ");
        scanf("%c", &yes);
    }

    return 0;
}

Answer:

You need to consume the trailling newline, enter remains in the stdin buffer ready to be read by the next scanf.

Change

scanf("%c", &yes);

to

scanf(" %c", &yes);

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