factorial.cpp

//Venix Cador
// bigint Test Program
//
// Tests:  int constructor, uses ==
//
#include "bigint.h"

#include <cassert>

//===========================================================================
int main()
{
  std::cout << "Testing factorial function!" << std::endl;

  {
    bigint bi = 1,
      result = 0;

    result = bi.factorial();

    assert(result == 1);

    std::cout << "Test: " << bi << "! == " << result << std::endl;
  }

  {
    bigint bi = 2,
      result = 0;

    result = bi.factorial();

    assert(result == 2);

    std::cout << "Test: " << bi << "! == " << result << std::endl;
  }

  {
    bigint bi = 3,
      result = 0;

    result = bi.factorial();

    assert(result == 6);

    std::cout << "Test: " << bi << "! == " << result << std::endl;
  }

  {
    bigint bi = 4,
      result = 0;

    result = bi.factorial();

    assert(result == 24);

    std::cout << "Test: " << bi << "! == " << result << std::endl;
  }

  {
    bigint bi = 5,
      result = 0;

    result = bi.factorial();

    assert(result == 120);

    std::cout << "Test: " << bi << "! == " << result << std::endl;
  }

  {
    bigint bi = 20,
      result = 0;

    result = bi.factorial();

    assert(result == bigint("2432902008176640000"));

    std::cout << "Test: " << bi << "! == " << result << std::endl;
  }

  {
    bigint bi = 50,
      result = 0;

    result = bi.factorial();

    assert(result == bigint("30414093201713378043612608166064768844377641568960512000000000000"));

    std::cout << "Test: " << bi << "! == " << result << std::endl;
  }

  {
    bigint bi = 100,
      result = 0;

    result = bi.factorial();

    assert(result == bigint("93326215443944152681699238856266700490715968264381621468592963895217599993229915608941463976156518286253697920827223758251185210916864000000000000000000000000"));

    std::cout << "Test: " << bi << "! == " << result << std::endl;
  }

  std::cout << "Done with testing factorial." << std::endl;
}