/*  This program implements the quincunx game or bean machine (this is sort of like a pacchinko machine if you 
 *  are familiar with those).  The user specifies some number of slots and the number of "beans" to drop (we
 *  refer to them as balls in this game).  The balls drop hitting pins which causes them to randomly bounce
 *  one position to the left or right.  The way the pins are set up, we actually move them by 1/2 a slot's
 *  position (see diagram below).  When they hit the bottom, they land in a slot.  We want to see, after all
 *  balls have dropped, how many balls are in each slot and output that as a diagram. */
 
 /* Let's assume 6 slots.  The pattern of pins is shown below.  Notice for every other row, the pins are either
  * directly above a slot or directly above a "wall" between the slots.  As a ball drops and hits a pin, it will
  * either bounce 1 location to the left (-.5) or 1 location to the right (+.5).  
  *       *
  *      * *
  *     * * *
  *    * * * *
  *   * * * * *
  * |_|_|_|_|_|_|  */

import java.util.*;								// need both Random and Scanner

public class Prog7_21
{
	public static void main(String[] args)
	{
		Scanner in = new Scanner(System.in);
		Random g = new Random();
		int size=0;
		int balls=0;
		size=get(in, "slots", 5, 10);			// get is a generic data verification input method, we use it to get
		balls=get(in, "balls", 5, 100);			// both the number of slots (between 5 and 10) and balls (between 5 and 100)
		int[] slots = new int[size];			// set up the slots, all of which are initially empty
		for(int i=0;i<size;i++) slots[i] = 0;
		int temp;								// temp is used to store the value returned from the drop method
		for(int i=0;i<balls;i++)				// for each ball:
		{
			temp = drop(g, size);				// drop it and see which slot it landed in
			slots[temp]++;						// increment that slot
		}
		output(slots, size);					// output is a method to output the resulting slots in terms of how many balls ended there
	}


	// follow the ball as it moves down the layers of pins.  There are size-1 layers for size slots.
	public static int drop(Random g, int size)
	{
		double location = size / 2.0;			// start the ball in the middle
		for(int j=0;j<size-1;j++){				// for each layer
			if(g.nextInt(2)==0)					// bounce it to the left or right by 1/2 a slot
				location=location-.5;
			else location=location+.5;
		}
		if(location<0) location=0;				// make sure it has not bounced outside of bounds, should not be possible
		else if(location>=size) location=size-1;	// but here to ensure no runtime error
		return (int)location;					// return the int value of location 
	}
	
	// input and data verify that the value being requested, as denoted by the String text, is between min and max
	public static int get(Scanner in, String text, int min, int max)
	{
		int temp = 0;
		do{
			System.out.print("Enter number of " + text + " between " + min + " and " + max + "  ");
			temp = in.nextInt();
		}while(temp<min||temp>max);
		return temp;
	}
	
	// output the balls in the slots
	public static void output(int[] slots, int size)
	{
		int max = getMax(slots, size);					// the tallest stack of balls will be max
		while(max>0) {									// work our way downward from max
			for(int i=0;i<size;i++)						// if this slot has at least max balls, output the ball as an O, otherwise output a blank
				if(slots[i]>=max)
					System.out.print("\t0");
				else System.out.print("\t");
			max--;										// decrement max to indicate one fewer balls for the next iteration through the slots
			System.out.println();						// output a blank line to start the next row of output
		}
	}
	
	public static int getMax(int[] slots, int size)
	{
		int max = slots[0];
		for(int i=1;i<size;i++)
			if(slots[i]>max) max = slots[i];
		return max;
	}
}