Question

Project 12, page 312 in DATA STRUCTURES and ABSTRACTIONS with JAVA BY FRANK M. CARRANO AND TIMOTHY M. HENRY

You will create two files: PascalTriangle.java and Driver.java. The Driver file will contain the main

method. The main method will ask the user what size triangle to create, that is to say how many rows

the triangle will have. It will then create an instance of the pascalTriangle class, passing the constructor

the number of rows. It will then loop to printout all the rows. If a size of 10 was entered it should

printout the following:

The Pascal Triangle of size 10 is

1

1 1

1 2 1

1 3 3 1

1 4 6 4 1

1 5 10 10 5 1

1 6 15 20 15 6 1

1 7 21 35 35 21 7 1

1 8 28 56 70 56 28 8 1

1 9 36 84 126 126 84 36 9 1

Be sure to follow the instructions for the PascalTriangle class in the book

Answer 1

input code:

driver.java

1 import java.util.*; 2 /*make Driver class which extends Pascal Triangle class*/ 3 public class Driver extends PascalTriangle 4- { public static void main(String[] args) /*create a Object*/ PascalTriangle p1=new PascalTriangle(10); /*call the method*/ p1.Triangle(); 12 }|

PascalTriangle.java

1 public class PascalTriangle { public static int n; /*make constructor*/ public PascalTriangle() Soovau AWN this.n=0; public PascalTriangle(int m) this.n=m; /*make method for print the Pascal Triangle*/ static void Triangle() 15 - for (int j = 0; j<n; j++) /*print the value in line*/ for (int i = 0; i <= j; i++) /*call value function and print the value*/ System.out.print(value(j, i)+" "); /*print the line*/ System.out.println(); /*make function for generate the value*/ public static int value(int m, int k) int ans = 1; /*check the condition*/ if (k > m - k) k = m - k; /*calculate the value*/ for (int i = 0; i < k; ++i) ans *= (m - i); ans /= (i + 1); /*return value*/ return ans;

output:

11 1 21 1 3 3 1 1 4 6 4 1 1 5 10 10 5 1 1 6 15 20 15 6 1 1 7 21 35 35 21 7 1 1 8 28 56 70 56 28 8 1 1 9 36 84 126 126 84 36 91 ... Program finished with exit code o Press ENTER to exit console.

code:

Driver.java

import java.util.*;
/*make Driver class which extends PascalTriangle class*/
public class Driver extends PascalTriangle
{
public static void main(String[] args)
{
/*create a Object*/
PascalTriangle p1=new PascalTriangle(10);
/*call the method*/
p1.Triangle();
}
}

PascalTriangle.java

public class PascalTriangle
{
public static int n;
/*make constructor*/
public PascalTriangle()
{
this.n=0;
}
public PascalTriangle(int m)
{
this.n=m;
}
/*make method for print the PascalTriangle*/
static void Triangle()
{
for (int j = 0; j < n; j++)
{
/*print the value in line*/
for (int i = 0; i <= j; i++)
{
/*call value function and print the value*/
System.out.print(value(j, i)+" ");
}
/*print the line*/
System.out.println();
}
}
  
/*make function for generate the value*/
public static int value(int m, int k)
{
int ans = 1;
/*check the condition*/
if (k > m - k)
k = m - k;
/*calculate the value*/
for (int i = 0; i < k; ++i)
{
ans *= (m - i);
ans /= (i + 1);
}
/*return value*/
return ans;
}
}