#include <iostream>
using std::cout;
using std::ios;
 
#include <iomanip>
using std::setw;
using std::setprecision;
using std::fixed;
using std::showpoint;
 
#include <cstdlib>
using std::rand;
using std::srand;
 
#include <ctime>
using std::time;
 
int main()
{
	const long ROLLS = 36000;
	const int SIZE = 13;
 
	// array expected contains counts for the expected
	// number of times each sum occurs in 36 rolls of the dice
	int expected[ SIZE ] = { 0, 0, 1, 2, 3, 4, 5, 6, 5, 4, 3, 2, 1 };
	int x; // first die
	int y; // second die
	int sum[ SIZE ] = { 0 };
 
	srand( time( 0 ) );
 
	// roll dice 36,000 times
	for ( int roll = 0; roll < ROLLS; ++roll )
	{
		x = 1 + rand() % 6;
		y = 1 + rand() % 6;
		++sum[ x + y ];
	}
 
	cout << setw( 10 ) << "Sum" << setw( 10 ) << "Total" << setw( 10 )
		<< "Expected" << setw( 10 ) << "Actual\n" << fixed << showpoint;
 
 
	// display results of rolling dice
	for ( int j = 2; j < SIZE; j++ )
		cout << setw( 10 ) << j << setw( 10 ) << sum[ j ]
			<< setprecision( 3 ) << setw( 9 )
			<< 100.0 * expected[ j ] / 36 << "%" << setprecision( 3 )
			<< setw( 9 ) << 100.0 * sum[ j ] / 36000 << "%\n";
 
 
	return 0; // indicates successful completion
} // end main