// Programmieren 1, Praktikum 4, Aufgabe 4
// Sven Eisenhauer
// 14.12.2004
//
// file: main.cpp
//
// purpose: Simulate a Galton Board
//

#include <iostream>

using std::cin;
using std::cout;
using std::endl;

#include <iomanip>

using std::setprecision;
using std::setw;

// contains function prototypes for functions srand and rand
#include <cstdlib>

#include <ctime> 

const int maxBoxes=100;
const int minBoxes=1;

int fall(int &,int &);
void getInput(int &,int &, char &);
void textOutput(int[], const int, const int);
void graphicalOutput(int[], const int, const int);

int main()
{
	srand(time(0));

	int nrBalls;
	int minBox,maxBox,nrBox;
	int box;
	int result[maxBoxes+1]={0};
	char outputMode;
	
	getInput(nrBalls,nrBox,outputMode);
	for (int i=1;i<=nrBalls;i++)
	{
		minBox=minBoxes;
		maxBox=nrBox;
		box=fall(minBox,maxBox);
		result[box]++;
	}
	if (outputMode=='t' || outputMode=='T')
		textOutput(result,nrBalls,nrBox);
	else
		graphicalOutput(result,nrBalls,nrBox);

	return 0;
}// end function main

void getInput(int& nrBa, int& nrBo, char &outpMode)
{
	cout << "Please enter number of boxes (max." << maxBoxes <<"): ";
	cin>>nrBo;	
	cout << "Please enter number of balls: ";
	cin>>nrBa;
	cout << "Please enter output mode: [T/t] table, [G/g] graphical: ";
	cin >> outpMode;
}// end function getInput

int fall(int &minB, int &maxB)
{
	// if we are not over last 2 boxes
	if((maxB-minB)>1)
	{
		if (0==rand()%2)
			// ball falls to the right => we cannot reach the most left box anymore
			minB++;
		else
			// ball falls to the left => we cannot reach the most right box anymore
			maxB--;
		fall(minB,maxB);
		//return 0;
	}
	// only 2 possible boxes left... the base case 
	else
	{
		if (0==rand()%2)
			// left box
			return minB;
		else
			// right box
			return maxB;
	}
}

void textOutput(int resArray[], const int balls,const int nrBox)
{
	//int sum=0;

	cout << endl << setw(10) << "Box" << setw(10) << "Balls" << setw(16) << "Norm." <<endl;
	for (int n=1;n<=nrBox;n++)
	{
		cout << setw(10) << n << setw(10) << resArray[n] << setw(16)<<static_cast <double>(resArray[n])/balls<<endl;
	//	sum+=resArray[n];
	}
	//cout << endl << "Sum: " << sum << endl << endl;
}// end function textOutput

void graphicalOutput(int resArray[], const int balls, const int nrBox)
{
	const int maxColumns=75;

	for (int n=1;n<=nrBox;n++)
	{
		cout << setw(2) << n << ": "; 
		for (int i=0;i<static_cast <int>(((static_cast <double> (resArray[n]))/balls)*maxColumns);i++)
			cout<<"*";
		cout << endl;


	}
}// end function graphicalOutput