Question

I’ve been attempting to convert a set of nested loops into a single equation and need some help.

The code to calculate my sequences is as follows:

`

int Astart = 1;
int Bstart = 1;
int Cstart = 1;
int Dstart = 1;

int Ai = 6;
int Bi = 2;
int Ci = 3;
int Di = 4;

int A,B,C,D = 0;

int i=0;
for(int a=Astart;a<Astart+Ai; a++)
{
    for(int b=Bstart;b<Bstart+Bi; b++)
    {
        for(int c=Cstart;c<Cstart+Ci;c++)
        {
            for(int d=DStart;d<Dstart+Di;d++)
            {
                std::cout << "[" << i << "]" << a << " " << b << " " << c << " " << d << std::endl;
                i++;
            }
        }
    }
}

`

All I need to do is have a single for loop running the number of permutations to replicate the behavior of the nested loop. i.e.

for(int i=0; i<(Ai*Bi*Ci*Di); i++)
{

<Insert equations here!>

}

What I’m really after is a function that takes an integer in the sequence and calculates the values of A,B,C and D based on the variables Ai,Bi,Ci,Di and Astart,Bstart,Cstart,Dstart.

Also, this system relies on the order of the nested loops, is there a method of not relying on the order to get the values A,B,C,D?

Any help would be great,

Thanks,

Chris.

Answer 1

Use the divide (/) and remainder (%) operators.

93 / 10 = 9
93 % 10 = 3

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