flip.cc From Astrachan, p 333
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#include <iostream.h>
#include "coin.h"
#include "prompt.h"

// verify random nature of Coin class, flip coin lots of times

int main()
{
    Coin theCoin; 

    long int numFlips = PromptRange("# coin flips",1,1000000);
    long int numHeads = 0;         // number of times 'heads' is flipped
    long int k;
    
    for(k=0; k < numFlips; k++)
    {
        if (theCoin.Flip() == heads)
        {  
            numHeads++;
        }
    }
    cout << "# of heads = " << numHeads << " : "
         << double(numHeads)*100/numFlips << "%" << endl;
    
    return 0;
}