// Example 6.12. Test program for randomDouble and randomDoubleRange   
   
#include <iostream>
#include <iomanip>
#include <cstdlib>   
   
using namespace std;

int main()   
{   
   double randomDouble();   
   double randomDoubleRange(double lowerBound, double upperBound);   
   
   int i = 0;   
   
   cout << "Random doubling point numbers in range\n";
   cout << setw(20) << "0-1" << setw(20) << "3-7" << "\n\n";   
   while (i < 10)   
   {
      cout << setw(20) << randomDouble() 
           << setw(20) << randomDoubleRange(3, 7) << endl;
      i++;
   }

   return 0;
}   

//
// Function to return a random double between 0 and 1
// Pre:  The generator is seeded.
// Post: A random double greater than or equal to 0
// 	  and less than 1 has been returned.
//

double randomDouble()
{
   return ( rand() / (static_cast<double>(RAND_MAX) + 1) );
}

//
// Function to generate a random double between lowerBound
// and upperBound
// Pre:  lowerBound and upperBound are of type double with
//       lowerBound < upperBound. The generator is seeded.
// Post: A random double greater than or equal to lowerBound
//       and less than upperBound has been returned.
//

double randomDoubleRange(double lowerBound, double upperBound)
{
   double random_0_1;   // random number between 0 and 1

   random_0_1 = rand() / (static_cast<double>(RAND_MAX) + 1);
   return ((upperBound - lowerBound) * random_0_1
	     + lowerBound);
}