How to choose numbers so that as a result, in the process of iteration in the loop, the variable does not acquire the value 0

Dears! I have got a problem with the measuring speed of the operation of division of my processor(How fast does the operation performs) Here I will do a code example, other functions work well so they shouldn't be touched

Code in C++ Assume that all headers, functions and classes are defined

double division()
{
    // some numbers of type int are required here with the names as in for-loop 
    for(long index = 0; index < Iterations; index++)
    {
        a4 = a10 / a2;
        a5 = a3 / a1;
        a4 = a5 / a1;
        a6 = a8 / a2;
        a3 = a6 / a2;
        a3 = a8 / a1;
        a1 = a2 / a10;
        a10 = a9 / a1;
        a7 = a6 / a1;
        a8 = a7 / a1;
    }
}

This function is defined in class IntType to measure the speed of the processor onto the operation of division with type integer. In the same way I need to write to other datatypes including char, long, double and float. Only for this one! In the output I always get 100% effectiveness with all data types which support division. The task is to determine the speed of the computer system Any help is appreciated