Interactive calculations.

//gcc 7.4.0

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

int main(void) {
    int num1, num2;

    printf("Enter 2 numbers: ");
    fflush(stdout);
    scanf("%d %d", &num1, &num2);
    // num1 = 44;
    // num2 = 7;

    long sum = num1 + num2;
    long dif = num1 - num2;
    long prd = num1 * num2;

    printf("%d + %d = %ld\n", num1, num2, sum);
    printf("%d - %d = %ld\n", num1, num2, dif);
    printf("%d * %d = %ld\n", num1, num2, prd);

    if (num2 != 0) {
        double quot = (double) num1 / (double) num2;
        div_t divvy = div(num1, num2);

        printf("%d / %d = %f\n", num1, num2, quot);
        printf("%d / %d = %d, rem %d\n", num1, num2, divvy.quot, divvy.rem);
    }
    else {
        printf("diivide by zero is illegal!\n");
    }

    return 0;
}