Looping operations

Question

I would like to write something like this;

for (op1 in (plus, minus, times, divby, exponent)) {
    printf("%d", a op1 b);
}

so that what actually ends up being executed is something like this

printf("%d", a + b);
printf("%d", a - b);
printf("%d", a * b);
printf("%d", a / b);
printf("%d", a ^ b);

How can I write this?

Answer 1

Array of function pointers would do.

double plus(int a, int b);
double minus(int a, int b);
double times(int a, int b);
double divby(int a, int b);
double exponent(int a, int b);

typedef double (*p_fun)(int a, int b);

int main()
{
    int a = 5, b = 10;
    p_fun pa[] = {plus, minus, times, divby, exponent};
    for( int i = 0; i < sizeof(pa)/sizeof(p_fun); i++ )
    {
        printf("%f\n", pa[i](a, b));
    }
    return 0;
}