Switch/Case exiting the code working when I type in the console C

Question

I am trying to make a basic console script for a calculator as a starter C project. When I type anything after the printf("\nOperator: "); Nothing happens it just exits the program. This shouldn't happen because of the switch statement at line 45

Language: C

Compiler: GCC

#include <stdio.h>
#include <math.h>
#include <string.h>
#include <Windows.h>

int main()
{



    // Variables

    int x;
    int y;
    char op = ' ';
    int sum;
    int difference;
    int product; 
    int quotient;
    int sqrta;
    int logarithm;
    int exponent;

    // Functions

    printf("**FxrMath**\n");
    printf("");
    printf("Options:\n");
    printf("(A)dd\n");
    printf("(S)ubtract\n");
    printf("(M)ultiply\n");
    printf("(D)ivide\n");
    printf("S(q)uare Root\n");
    printf("(L)ogarithm\n");
    printf("(P)ower (x^y)\n");
    printf("(H)ypotoneuse Calculator");
    printf("\n");
    printf("\n**OPERATOR MUST BE LOWERCASE**");
    printf("\n");
    printf("\nOperator: ");
    scanf("%d", &op);

    

    switch (op) // Checking what to do
    {
        case 'a':
            printf("First Number: ");
            scanf("%d", &x);
            printf("\nSecond Number: ");
            scanf("%d", "&d", &y);

            int sum = x + y;

            printf("\n%dSum: ", sum);
            Sleep(2500);
            break;
    

        case 's':
            printf("First Number: ");
            scanf("%d", &x);
            printf("\nSecond Number: ");
            scanf("%d", &y);

            int difference = x - y;

            printf("\n%dDifference: ", difference);
            Sleep(2500);
            break;


        case 'm':
            printf("First Number: ");
            scanf("%d", &x);
            printf("\nSecond Number: ");
            scanf("%d", &y);

            int product = x * y;

            printf("\n%dProduct: ", product);
            Sleep(2500);
            break;
            
        
        case 'd':
            printf("First Number: ");
            scanf("%d", &x);
            printf("\nSecond Number: ");
            scanf("%d", &y);

            int quotient = x / y;

            printf("\n%dQuotient: ", quotient);
            Sleep(2500);
            break;
            

        case 'q':
            printf("Number: ");
            scanf("%d", &x);

            int sqrta = sqrt(x);

            printf("\n%dSquare Root: ", sqrta);
            Sleep(2500);
            break;
            

        case 'l':
            printf("First Number: ");
            scanf("%d", &x);

            int logarithm = log(x);

            printf("\n%dLogarithm: ", logarithm);
            Sleep(2500);
            break;
            

        case 'p':
            printf("First Number: ");
            scanf("%d", &x);
            printf("\nSecond Number: ");
            scanf("%d", &y);

            int exponent = pow(x, y);

            printf("\n%dExponent: ", exponent);
            Sleep(2500);
            break;
            

        case 'h':
                int a;
                int b;

                printf("\nA: ");
                scanf("%d", a);
                printf("\nB: ");
                scanf("%d", b);

                double hypotenuse  = sqrt((a*a) + (b*b));

                printf("\n%dHypotenuse: ", hypotenuse);
                Sleep(2500);
                break;
            

        default:
            break;
        }


    return 0;
}

Answer 1

The variable op is declared as having the type char

char op = ' ';

So this call of scanf

scanf("%d", &op);

is incorrect. Firstly the function expects an argument of the type int and secondly entering a symbols will not be successful.

Instead write

scanf( " %c", &op );

Pay attention to the leading space in the format string. It allows to skip automatically white space characters in the input buffer.

Also such a call of scanf

scanf("%d", "&d", &y);

also is incorrect. It seems you mean

scanf("%d", &y);

And these variable declarations

int sum;
int difference;
int product; 
int quotient;
int sqrta;
int logarithm;
int exponent;

are redundant because in each code snippet under a case label you declared a corresponding variable one more as for example

    case 'a':
        printf("First Number: ");
        scanf("%d", &x);
        printf("\nSecond Number: ");
        scanf("%d", "&d", &y);

        int sum = x + y;
        ^^^^^^^
        

And such declarations must be enclosed in block scopes as for example

    case 'a':
    {
        printf("First Number: ");
        scanf("%d", &x);
        printf("\nSecond Number: ");
        scanf("%d", "&d", &y);

        int sum = x + y;
        //...
        break;
     }