Brtdku

The below C program gives me output only for Addition(+), difference(-), multiplication(*).
But when I try to use division(/) and modulus(%) the program just close itself without giving any error. Help me I'm a newbie to C programming.

//A simple calculator.



#include<stdio.h>

#include<conio.h>

void main()

{

int a, b, sum, diff, rem, multi;

float div;

char character;

clrscr();

printf("Choose the character you want to use(+, -, *, /, %): ");

scanf("%c", &character);

switch(character)

{

case '+': //will be used for addition.

    printf("Enter the first and second number: ");

    scanf("%d %d", &a, &b);

    sum = a+b;

    printf("The sum of the %d and %d is %d", a, b, sum);

    break;

case '-': //will be used for difference.

    printf("Enter the first and second number: ");

    scanf("%d %d", &a, &b);

    diff = a-b;

    printf("The difference between %d and %d is %d", a, b, diff);

    break;

case '%': //will be used for modulus.

    printf("Enter the first and second number: ");

    scanf("%f %f", &a, &b);

    rem = a%b;

    printf("The remainder of %f and %f is %f", a, b, rem);

    break;

case '*': //will be used for product of 2 no.

    printf("Enter the first and second number: ");

    scanf("%d %d", &a, &b);

    multi = a*b;

    printf("The multiplication of %d and %d is %d", a, b, multi);

    break;

case '/': //will be used for the division.

    printf("Enter the first and second number: ");

    scanf("%f %f", &a, &b);

    div = a/b;

    printf("The division of %f and %f is %f", a, b, div);

    break;

default:

    printf("Error! character please retry");

}

getch();

}

You are using %f format specifier for int variables in / and % cases.

scanf("%f %f", &a, &b);

Thus invoking undefined behavior.

Change it to as below.

scanf("%d %d", &a, &b);

%f is used to readin the float variables.

If you want float result for division, you need to cast the one of the argument to float instead reading them as float.

  div = (float)a/b;

When using the / and % use

scanf("%d %d", &a, &b);

instead of

scanf("%f %f", &a, &b);

because %f is used for float vars whereas in case of / and % %d is used

You are using wrong formats. After enabling -Wall in gcc and fixing the warnings I get a working program. You also missing the n in your answer printf()'s

#include <stdio.h>



int main(int argc, char **argv)

{

  int a, b, sum, diff, rem, multi;

  float div;

  char character;

  printf("Choose the character you want to use(+, -, *, /, %%): ");

  scanf("%c", &character);

  switch(character)

    {

    case '+': //will be used for addition.

      printf("Enter the first and second number: ");

      scanf("%d %d", &a, &b);

      sum = a+b;

      printf("The sum of the %d and %d is %dn", a, b, sum);

      break;

    case '-': //will be used for difference.

      printf("Enter the first and second number: ");

      scanf("%d %d", &a, &b);

      diff = a-b;

      printf("The difference between %d and %d is %dn", a, b, diff);

      break;

    case '%': //will be used for modulus.

      printf("Enter the first and second number: ");

      scanf("%d %d", &a, &b);

      rem = a%b;

      printf("The remainder of %d and %d is %dn", a, b, rem);

      break;

    case '*': //will be used for product of 2 no.

      printf("Enter the first and second number: ");

      scanf("%d %d", &a, &b);

      multi = a*b;

      printf("The multiplication of %d and %d is %dn", a, b, multi);

      break;

    case '/': //will be used for the division.

      printf("Enter the first and second number: ");

      scanf("%d %d", &a, &b);

      div = a/b;

      printf("The division of %d and %d is %fn", a, b, div);

      break;

    default:

      printf("Error! character please retry");

    }

}

Test output:

$ ./dummy

Choose the character you want to use(+, -, *, /, %): %

Enter the first and second number: 5 2

The remainder of 5 and 2 is 1

$