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it's my homework and i have no clue what i'm doing. i pay attention in class but i still don't know what's going on! it's a 2 part project, with a cointoss class and histogram class.

this is my cointoss class

```
import java.util.Scanner;
public class CoinToss {
private static final int MIN_HEADS = 0; // minimum number of heads per set
/**
* main method:
* ask the user how many sets of coin flips and how many flips per set
* count occurances of heads in user specified number of sets of coin flips
* draw a horizontal and vertical histogram of the number of heads
*/
public static void main(String[] args) {
// set up to get user input
Scanner scan = new Scanner(System.in);
// ask user for the number of sets of coin flips
System.out.println("How many sets of coin flips do you want?");
int nSets = scan.nextInt();
// ask user for the number of coin flips per set
System.out.println("How many coin flips per set do you want?");
int nFlips = scan.nextInt();
// maximum number of heads that can occur is number of flips
int maxHeads = nFlips;
// calculate maximum length of histogram bars based on number of flips per set
// based on finding the number of combinations for half heads / half tails
// n!
// formula is ----------- with r = n/2
// r! (n-r)!
int maxLength = factorial (nFlips) /
(factorial (nFlips / 2) * factorial (nFlips - nFlips / 2));
// instantiate a coin object named myCoin
Coin myCoin = new Coin();
// step 1:
// declare an int array named "counts" to count coin flip occurences
// make its size one larger than maxHeads
int counts[] = new int [maxHeads + 1];
// step 2:
// initialize all of the values in the array to 0
for(nFlips=1;nFlips<=maxHeads;nFlips++);
counts[nFlips] = 0;
// step 3:
// flip the coin for n sets with nFlips flips per set
// count the number of heads in each set (heads = 1, tails = 0)
for (int i = 0; i < nSets; i++)
{
int sum = 0;
for (int j = 0; i <nFlips; j++)
{
sum = sum +(myCoin.flip()? 1:0);
}
}
// step 4:
// print out the estimated probabilities of all heads and all tails
System.out.println((float) counts [MIN_HEADS] / nSets);
// step 5:
// instantiate an object of the Histogram class with
// the array to be drawn, the indices of valid data,
// and the maximum length of the bars in the histogram
//
// call its two draw methods to draw the two histograms
int maxCount = 0;
for (int i = MIN_HEADS; i < maxHeads +1; i++)
{
if(maxCount <= counts [i])
{
maxCount = counts [i];
}
break;
}
}
// function to calculate factorial of n
public static int factorial(int n)
{
int factorial = 1;
// write the code for a loop to calculate factorial of n here
while(n!=1);
{
factorial=n*(factorial);
n--;
}
return factorial;
}}
/*201020*/
```

and this is my histogram class

```
public class Histogram
{
private int [] values;
private int minIndex;
private int maxIndex;
private int maxLength;
/** constructor for histogram drawing class
* @param values the array of integer values to draw
* @param minIndex the lowest index in the array for the range to draw
* @param maxIndex the highest index in the array for the range to draw
* @param maxLength the length of line to draw for the largest value
*/
public Histogram(int [] values, int minIndex, int maxIndex, int maxLength)
{
// initialize the values of the instance variables from the constructor parameters
this.values = new int [maxIndex + 1]; // allocate memory for a copy of the values array
this.minIndex = minIndex;
this.maxIndex = maxIndex;
this.maxLength = maxLength;
// step 6:
// find largest number in values array for scaling length of bars
int MaxValue = values[0];
for(int i=minIndex; i<=maxIndex; i++)
{
if (values[i] > MaxValue)
MaxValue = values[i];
}
// step 7:
// copy data from values array to this.values array while scaling to maximum length of bars
System.arraycopy(values,0,this.values,0,values.length);
}
/** draw a horizontal bar graph
*/
public void drawHor()
{
// step 8:
// draw horizontal bar graph (one line per roll value)
for (int i = 1; i<values.length; i++)
System.out.print("Value " + i + ":" + "\t" + values[i]);
System.out.println("*");
}
/** draw a vertical bar graph
*/
public void drawVer()
{
// step 9:
// draw vertical bar graph (one column per roll value)
for (int i = 1; i<values.length; i++)
System.out.print("Value " + i + ":" + "\t" + values[i]);
System.out.println("*");
}
}/*201020*/
```

any help would be greatly appreciated! i have no clue what im doing!