/* 

  Program: Type Conversion — Integer Division vs Explicit Cast (U1)

  What it does:

    - Reads two integers a and b.

    - Prints: (1) a/b as integer division, (2) (float)a/b, (3) a/(float)b, (4) (double)a/b.

    - Explains that when both operands are integers, C performs integer division (truncation toward zero).

    - Any cast to float/double promotes the operation to floating-point division (keeps the fractional part).

  Note: Guard against division by zero.

*/

#include <stdio.h>

int main(void) {

    int a, b;

    int intDiv;

    float fDiv1, fDiv2;

    double dDiv;

    printf("Enter two integers (a b): ");

    if (scanf("%d %d", &a, &b) != 2) {

        printf("Invalid input. Please enter exactly two integers.\n");

        return 0;

    }

    if (b == 0) {

        printf("Error: division by zero is undefined.\n");

        return 0;

    }

    /* (1) Integer division: fractional part is discarded (truncation toward zero). */

    intDiv = a / b;

    /* (2) & (3) Casting either operand to float promotes the operation to float division. */

    fDiv1 = (float)a / b;     /* Cast numerator */

    fDiv2 = a / (float)b;     /* Cast denominator */

    /* (4) Casting to double gives a double-precision result. */

    dDiv  = (double)a / b;

    printf("Integer division (a/b)      = %d\n", intDiv);

    printf("Float division ((float)a/b) = %.6f\n", fDiv1);

    printf("Float division (a/(float)b) = %.6f\n", fDiv2);

    printf("Double division ((double)a/b) = %.10f\n", dDiv);

    /* Tip:

       Another common idiom is multiplying by 1.0 to force floating-point: 1.0 * a / b

       Example check:

         For a=7, b=2 -> intDiv = 3, float/double divisions = 3.5

    */

    return 0;

}