really big numbers

I have a program here that doubles .01 64 times. After a while, the numbers start to come out in scientific notation. Is there a type of variable or something that does not do this? I am new to C++, so please make any replies easy to understand. The bold area of the code is the part that displays in scientific notation. Here is the program:

Code:

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#include <iostream>
#include <cstdlib>

using namespace std;

int first(void);
int bonus(void);

int main(void)
{
        unsigned int response;

        cout<<"Checkerboards and Bacterial Reproduction Problem Solver\nby Drew Harris";

        do
        {
                cout<<"\n\nSelect an Option:\n"
                        <<"1) Answer Questions 1, 2, and 3"<<endl
                        <<"2) Answer the bonus question"<<endl
                        <<"3) Exit"<<endl;
                cin >>response;
                switch(response)
                {
                case 1:
                        cout<<endl<<endl;
                        first();
                        break;
                case 2:
                        cout<<endl<<endl;
                        bonus();
                        break;
                default:
                        cout<<endl<<"That is not a menu choice";
                }
        }while(response != 3);
        cout<<"\nThat's how I solved the checkerboard questions."<<endl;
        system("pause");
        return 0;
}

int first(void)
{
        double totalmoney = .01;
        unsigned int cursquare = 1;

        cout<<"1 | 0.01"<<endl;

        while(totalmoney<=21.00)
        {
                totalmoney = totalmoney * 2;
                cursquare++;
                if(totalmoney>21.00)
                {
                        break;
                }
                cout<<cursquare<<" | "<<totalmoney<<endl;
        }
return 0;
}

int bonus(void)
{
        double totalmoney = .01;
        unsigned int cursquare = 1;

        cout<<"1 | 0.01"<<endl;

        while(cursquare<64)
        {
                totalmoney = totalmoney * 2;
                cursquare++;
                cout<<cursquare<<" | "<<totalmoney<<endl;
        }
        return 0;
}


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In any function using cout or in main( ), use this code:

Code:

---

cout.precision(20);  // 15 is ok

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Anything past the 15th digit is not really that accurate.

See this:
http://support.microsoft.com/default...b;EN-US;q42980

to tell you why.

Thanks. That's exactly what I needed.