Need this coded in C++ language: package Chapter_07; import java.util.Scanner; /

Question

Need this coded in C++ language:

package Chapter_07;

import java.util.Scanner;

/**
* Chapter 7 Exercise 21:
*
* (Game: bean machine) The bean machine, also known as a quincunx
* or the Galton box, is a device for statistics experiments named after
* English scientist Sir Francis Galton. It consists of an upright board
* with evenly spaced nails (or pegs) in a triangular form.
* Each ball takes a random path and falls into a slot.
*
* Balls are dropped from the opening of the board. Every time a ball hits a nail,
* it has a 50% chance of falling to the left or to the right. The piles of balls
* are accumulated in the slots at the bottom of the board.
* Write a program that simulates the bean machine. Your program should prompt the user
* to enter the number of the balls and the number of the slots in the machine.
* Simulate the falling of each ball by printing its path.
*
* (Hint: Create an array named slots. Each element in slots stores the number of balls
* in a slot. Each ball falls into a slot via a path. The number of Rs in a path is the
* position of the slot where the ball falls. For example, for the path LRLRLRR, the ball
* falls into slots[4], and for the path is RRLLLLL, the ball falls into slots[2].)
*
*/
public class Exercise_21 {

public static void main(String[] args) {

Scanner input = new Scanner(System.in);

System.out.print("Enter the number of balls to drop: ");
int numberOfBalls = input.nextInt();
String[] ballPaths = new String[numberOfBalls];

System.out.print("Enter the number of slots in the bean machine: ");
int numberOfSlots = input.nextInt();
int[] slots = new int[numberOfSlots];

// display ball paths
for (int i = 0; i < numberOfBalls; i++) {
ballPaths[i] = dropBall(slots);
System.out.printf("%10s ", ballPaths[i]);
}

// display game
System.out.println("");
printArray(slots, numberOfBalls);
}

public static String dropBall(int[] slot) {

StringBuilder ballPath = new StringBuilder();

for (int i = 0; i < slot.length - 1; i++) {
int random = (int)(Math.random() * 10) % 2;
if (random > 0) ballPath.append("R");
else ballPath.append("L");
}
int position = getBallPosition(ballPath.toString(), 'R');
slot[position]++;
return ballPath.toString();

}

public static int getBallPosition(String str, char a) {

int count = 0;
for (int i = 0; i < str.length(); i++) {

if (str.charAt(i) == a) count++;

}

return count;
}

public static void printArray(int[] slots, int numberOfBalls) {

while (!isEmpty(slots)) {

if (isRowEmpty(slots, numberOfBalls)) {
numberOfBalls--;
continue;
}
for (int i = 0; i < slots.length; i++) {

if (slots[i] >= numberOfBalls) {
System.out.printf("%2c", 'O');
slots[i]--;
}
else System.out.printf("%2c", ' ');

}
numberOfBalls--;
System.out.println("");

}

}

public static boolean isEmpty(int[] slots) {

for (int slot : slots) {
if (slot != 0) {
return false;
}
}

return true;
}

public static boolean isRowEmpty(int[] slots, int rowNum) {

for (int slot : slots) {
if (slot == rowNum) {
return false;
}
}

return true;
}

}

Explanation / Answer

#include <iostream>
#include <string.h>
#include <math.h>
#include <stdlib.h>
#include <iomanip>
#include <time.h>
#include <stdio.h>
using namespace std;

int getBallPosition(string str, char a)
{
int count = 0;
for (int i = 0; i < str.size(); i++)
{
if (str[i] == a) count++;
}
return count;
}

string dropBall(int slot[], int numberOfSlots)
{
string ballPath = "";
for (int i = 0; i < numberOfSlots - 1; i++)
{
int r = (rand()*10 +1) % 2;
if (r > 0) ballPath = ballPath+ "R";
else ballPath = ballPath+ "L";
}

int position = getBallPosition(ballPath, 'R');
slot[position]++;
return ballPath;

}
  
  
  

bool isEmpty(int slots[], int numberOfSlots)
{
for (int i = 0; i < numberOfSlots ; ++i)
{
if(slots[i] !=0) return false;
}
return true;
}

bool isRowEmpty( int slots[], int rowNum, int numberOfSlots)
{
for (int i = 0; i < numberOfSlots; ++i)
{
if(slots[i] == rowNum) return false;
}
return true;
}

void printArray( int slots[], int numberOfBalls, int numberOfSlots)
{
while (!isEmpty(slots,numberOfSlots))
{

if (isRowEmpty(slots, numberOfBalls, numberOfSlots))
{
numberOfBalls--;
continue;
}

for (int i = 0; i < numberOfSlots; i++)
{
if (slots[i] >= numberOfBalls)
{

printf("%2c",'O');
  
slots[i]--;
}

else
{ printf("%2c",' ');

}
}

numberOfBalls--;
cout << ""<<endl;
}
}
  
  

int main()
{
srand (time(NULL));
int numberOfBalls;
int numberOfSlots;
cout<< "Enter the number of balls to drop: ";
cin >> numberOfBalls;

string ballPaths[numberOfBalls];

cout<<"Enter the number of slots in the bean machine: ";
cin >> numberOfSlots;

int slots[numberOfSlots];
for (int i = 0; i < numberOfSlots; ++i)
{
slots[i]=0;
}

// display ball paths
for (int i = 0; i < numberOfBalls; i++)
{
ballPaths[i] = dropBall(slots,numberOfSlots);
printf("%10s ",ballPaths[i].c_str());
}
// display game
cout<<""<<endl;

printArray(slots, numberOfBalls, numberOfSlots);

return 0;
}

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